Everything you need to know about Digital Assets

A systematic exploration and discussion of digital assets

A systematic exploration and discussion of digital assets

Digital assets are becoming a central topic for discussion on the intersection of digital economies and open finance. The emergence of blockchain technology has redefined digital assets, creating new opportunities while also bringing tough challenges for newbies into this space to understand the concept. What are digital assets? What is the difference between decentralized digital assets versus their old, centralized counterparts? How did these differences occur, and what impact will they make? This article is devoted to a systematic exploration and discussion of the issues mentioned above concerning digital assets.

1.Definition of “Assets”

To discuss what “digital assets” refer to, we should first discuss what “assets” refer to. Unfortunately, there is no clear nor authoritative definition of assets in Chinese law literature, but there are a few fairly well-thought-out and enlightening views. We hightlight two pieces of them as follows:

Professor Zejian Wang, a Chinese authority on civil law, defines “assets” as:

Reference definition 1: a collection of rights with monetary value.

The Ministry of Finance of the People’s Republic of China defines “assets” as:

Reference definition 2: “resources formed by past transactions or events of firm; controlled or owned by the firm, and expected to bring economic benefits to the firm”.

The definition by Prof. Wang’s (reference definition 1) is significant in pointing out that assets are a “collection of rights”, that is, assets are a set of inter-related rights, which only exist in the level of human consciousness and law, and are not in any form of physical objects. It requires profound insights that we must distinguish the right aggregation as an asset from the ontological, tangible object from which this set of rights derives. However, this definition also has obvious shortcomings: “monetary value” is a rather vague concept.

The definition of the Ministry of Finance (reference definition 2) has some edges: 1) it points out that assets are resources that are expected to bring economic benefits. The keyword here is “expected”, which implies that the economic value does not need to be realized and even actually exist instantaneously. As long as the assets fit into the subjective judgment or even speculation in just a few people’s heads, it can be considered as “assets”. 2) It points out that the assets must be controlled or owned by and entity and should not be in the state of “dangling” ownerless. 3) It points out that assets are generated from the past “transactions or events”. The meaning of “events” is not clear, but it can be clear that assets can be created only through transactions, legal resolution and other contractual acts. However, the definition also has two prominent flaws: 1) it only defines the corporate assets, that is, the assets owned by legal persons, not natural persons. Of course, this is not a big problem. It can be easily expanded to cover natural persons and households. 2) A more serious problem is to define assets as “resources”. It is not only vague but also a mistake — it defines assets as “things” instead of derived rights.

Based on the advantages of the two referenced definitions, we propose the following definition:

Assets are a collection of rights. Assets: 1) are formed and adjusted by transactions or other contractual behaviors; 2) is clearly owned or controlled by an entity or a group of entities; 3) is expected to generate economic benefits.

For the above definition, it is necessary to make the following explanation:

First of all, assets must have expected economic returns. Here “expected” is a keyword. Something can still be an asset even if it does not deliver any cash flows or holds any solid economic benefits,as long as there is, at the present moment, an expected value greater than zero for its future economic income. This shows that the phrase “asset” is purely a subjective judgment, and, in its essence, a mere guess. From here, there is also an important corollary, that is, there must be an arrangement for the distribution of assets. Since people expect future returns from the assets, the arrangement must be made in advance, no matter whether the income is generated or not.

Second, in this definition, we adopt Professor Wang’s definition that assets are a collection of rights. This is certainly more accurate, but it will also bring some inconvenience in practice. For example, we usually say “this house is John’s asset”. According to the definition above, this statement is wrong. The correct statement should be “the combination of the ownership, control and other civil rights bound to this house is John’s assets”. However, it is unrealistic to force people to change their language habits in order to pursue semantic accuracy. Therefore, we can accept such a statement, but we should also make it clear that this is actually a lazy and simplified statement. The essence of this “asset” is the collection of rights derived from the backing objects. This is an important question to help us better understand “assets”.

Third, this definition requires a clear owner or controller, that is to say, there is an entity that decides the arrangement and disposal of assets. Among them, “clear” is a key requirement, and its significance lies in that for any asset, there must be a certain subject to control its ownership or control right. An entity is either the controller or not, there is not a blurry state — only binary. In addition, there is an important corollary that the status of assets is changeable and controllable. Because if the state of an asset cannot be changed or controlled, then the so-called owner or controller is meaningless.

Fourth, the creation and adjustment of assets are realized through transactions or other contractual behaviors. This explains the source of the assets and how the owner or controller controls the change in the state of the assets. Transactions are easy to understand, but how can we parameterize and understand “contractual behaviors”? Such behaviors include private contracts, laws and regulations, articles of association, ethic and ethnic customs and even general consensus. In a word, the state adjustment of assets always needs to be carried out by some definite procedure and protected or even confirmed by external rules.

Fifth, assets can be symbolized or even materialized. It has been pointed out that assets are actually a collection of rights, rather than the backing objects deriving such rights (land itself is not an asset, but the ownership of land is an asset). However, this is not to say that assets can only be intangible. Assets can be symbolized or even materialized. Money, stocks, options, bonds, notes, land title and so on, are the symbols or materialized representations of assets. This certificates or tokens are nothing more than representations of parts or all of the underlying assets. Therefore, as for assets, we should clearly distinguish between its basic tangible item (land), its definition as a collection of rights (land ownership), and its materialized representation (title deed). This conceptual clarity is very important for the following discussion of digital assets.

We can apply the definition of assets above to examine in some interesting scenarios.

For example, generally speaking, a piece of land is undoubtedly tangible assets. However, imagine two parties, A and B, just discover a new continent and face a piece of virgin land, they fight each other to win the ownership of the land. Now, before the fighting, was this land an asset? According to the definition, there is no clear controller of this land at this moment. Therefore, this piece of land without ownership is not an asset right now. Certainly, just in the near future, one party may obtain the control of this land and turn it into assets.

Is health a piece of assets? Slogans like “your health is the most valuable asset of you” are on every billboard in gyms. Really? We can think that health can generate expected economic benefits, but is health an aggregation of rights? Can health status be adjusted by trade or contractual acts? It seems that they are all out of the question. Health, therefore, should not be considered as assets, even if the commercials say so.

Another example, if someone is a crazy fan of something and has a collection of memorabilia items, but everyone in the world thinks that the collection is worthless, is the ownership of the collection an asset? A lot of people would say no. However, we can see from the definition that assets are extremely subjective. If a person subjectively expects that the goods will have economic benefits in the future, even if the rest of the world does not agree, this collection is also a piece of assets to him. To understand this, imagine that a person anticipates that someone else might suddenly be interested in the item they have in the future and may ask for it for a higher price. Another way to comprehend the fact is imagining if the item is lost, the person is willing to pay a certain amount of money to retrieve it. In this way, such a collection does have the expected economic benefits (or avoid future economic costs by holding it), and therefore it is indeed a piece of assets.

2. Expression of assets

In the discussion above, we have pointed out that assets are a collection of rights, which is abstract to some extent but can be expressed symbolically and materialized. We also pointed out that standardized bill such as banknotes, securities and land titles are all expressions of assets. However, if we go back to the source, we will realize that contracts are the fundamental expressions of assets, and official certificates are just standard contracts with a high degree of standardization.

For example, if a loan agreement is signed between two parties, then it is an asset to the creditor. The agreement is not necessarily standardized forms, instead, it can be a handwritten IOU note with both parties’ signatures or fingerprints. However, as long as it meets the basic requirements of the contract, it could be protected by law or custom and become the simplest materialized expression of assets.

This expression and protection of assets have been the case and logical foundation and the basis of most civil laws throughout history.

Some 5,000 years ago, Sumerian wrote contracts on clay tablets. Since these ancient times, textual contracts have been fully employed in all the major civilizations in the East and the West. Once contract technology came into being, it has become the main form of expressing the ownership of rights, debt relationship and other assets.

In the development of contract technology itself, there has been an ever-evolving process from general to specific, from heterogeneity to homogeneity, from non-standardization to standardization.

Non-standardized and general contracts appeared first, then did standard contracts. At first, they were established by convention, then the schema, protocol and standard forms of the contracts were imposed by laws and regulations or industry standards so that both parties only need to fill in some blanks to customize the contracts instead of drafting and negotiating on everything. This greatly improved the efficiency of making contracts and reduces transaction costs. The textual contracts physicalize agreements, enabling the permanent storage and exchange of contracts.

Bills are a special type of standardized contract. The killer feature of bills is the brevity. A bill can be printed on a small slip of paper. This does not mean that the contract terms of the ticket must be short, but more importantly, because of the higher degree of standardization for bills, a wider consensus or default base has been set. Therefore, many provisions and key terms on the usage of the bills do not need to be printed on the slip of paper but are placed somewhere outside the ticket, with common agreements or clear specifications. For example, for invoices, cheques, promissory notes, bills of exchange, pawn tickets and other documents, as well as ID cards, household registration, education certificates and other documents, the state has special legal provisions to regulate them. There is no need to repetitively print them on the tickets so that the bills and certificates themselves can be very simple, and easy to use for the layman.

Securities are a special subset of bills, which are usually anonymous and standardized homogeneous bills. Therefore, they carry low knowledge barriers and transaction frictions for users, that is to say, they have good liquidity. However, the most important significance of securities is their absolute fungibility, that is to say, the essence of the same kind of securities of any two units is exactly the same and cannot be distinguished. Due to this characteristic, securities simplify the abstract rights of assets expressed into one-dimensional objects and reduce the complex trade-off of multi-party interests into the calculation of quantitative relations. In this way, mathematics, the most powerful logical tool, can be introduced into the asset world. Its significance cannot be overemphasized.

Finally, the currency note is a special kind of securities, which is a standardized contract with the highest liquidity and widest consensus. Its most important feature is that, in the past, the government acts as the issuer of all value denominations and forces the notes to be accepted as legal tender unconditionally. China’s earliest banknotes, such as jiaozi in the Song Dynasty and Baochao in the Yuan and Ming Dynasties, wrote contract terms on the paper explicitly.

Jiaozi in the Northern Song Dynasty
Baochao in the Yuan and Ming Dynasties

For the US dollar, the terms are simplified to one sentence:


The terms on the US dollar

The discussion about currency is always full of heated debates. We have no intention of stepping into the debates over the nature and origin of money, nor do we imply that money has evolved solely from contracts in history. In fact, the development of the two is intertwined with each other throughout history, and it may not be possible to discuss which came first. Zhou Ziheng, a Chinese monetary scholar, once argued that currency was a balance payment instrument in the earliest stages of civilization, which was used in conjunction with contracts. The evolution of money into the primary form of full payment is actually the result of the recent development of civilization. But now that both of them have developed to a highly mature stage, we should realize, when we construct the whole system conceptually, that, as far as trading instruments are concerned, contracts are basic and general while currencies are advanced and special. However, the special abstraction of money strongly embodies the concept of value in transactions, enabling it to be widely used, and that us contemporary people are more familiar with it on an everyday basis compared to contracts.

The key point here is that we construct a progressive conceptual structure of concentric circles, that is, a contract is the most basic and general expression of assets, a standardized contract is a special form of contract, a bill is a special form of standardized contract, securities are a special form of bills, and the currency note is a special form of securities. The relationship between the five is shown in the following figure:

Five expressions of assets

We have finished the discussion of traditional assets and their features, evolution, and distinctions. Now it is time to address the topic of digital assets.

3. Analysis of digital assets

At present, popular definitions on the web do not distinguish digital assets from digital contents. Thus, all kinds of digital documents, images, audios and videos can be considered as digital assets.

However, according to the aforementioned discussion, assets are essentially a group of rights. Therefore, digital assets are an aggregate of economic rights derived from digital objects, not the digital objects themselves. So far, most of the discussions on digital assets do not distinguish the two.

Blockchain technology has redefined the way we digitally describe economic rights. Smart contracts and token on blockchains are much better technology to express assets, hence are much better technology to represent digital assets.

Let’s start with assets based on digital content. Since the assets can only be a group of rights in essence, then the digital content itself cannot become an asset, and only a set of rights attached to the digital content can be assets. In other words, this kind of digital assets is actually traditional assets derived from digital objects.

It should be noted that the expression of assets based on digital content is not necessarily digital, it can also be expressed in traditional paper contracts and paper bills. For example, we establish and distribute the copyright of a digital film in the form of a paper contract. It is backed by digital contents, but the asset itself is expressed in the form of a paper contract. As discussed, such assets are not digital assets, but traditional assets backed by digital objects.

Now we move on to the discussion of the digital representation of assets.

The so-called digital expression of assets is to digitalize the expression of assets in the previous section. For example, contracts originally expressed in paper and text can be digitalized into PDF files. A printed boarding pass can be expressed into an electronic boarding pass stored in your smartphone. The paper stock certificates of the past have been replaced with data records in a database. Paper banknotes are digitalized into balance in your Alipay account. Paper land titles are replaced by records in the national real estate registration database. These are digital representations of assets. However, the backing objects of these digital assets may be non-digital things, such as housing, equity, money, etc. Of course, its backing objects can also be digital content, such as a digital movie, a digital photo, an online novel, etc.

The difference between the two is very clear. The asset expression of a digital object is not necessarily digital, while the backing object of a digital asset expression is not necessarily digital either. But of course, there is an intersection between the two. If the backing object of an asset is digital and the asset expression is also digital, then it belongs to both categories.

So, when people say “digital assets”, which on early do they mean? The assets attached to digital content or the digital expression of assets?

We hold an unambiguous attitude towards the latter definition, that is, digital assets should refer to the digital expression of assets. If digital assets are positioned as assets based on digital content, it will only be a small category of traditional assets. After the emergence of blockchain technology, positioning digital assets as the digital expression of assets would open a new world for digital assets, open finance and even the whole digital economy. In order to give “digital assets” a bigger stage, we suggest that digital assets should be strictly referred to the digital expression of assets, and assets based on digital content should be called “digital content assets”.

The emergence of blockchain technology opens a new door to the world of digital assets. We must reexplore the significance of blockchain as an expression tool for assets.

4. Blockchain is THE platform for contract digitalization

There are many different views on the essence of blockchain. Some people think it is distributed ledger technology, some define it as a kind of data management technology with specific features, others define it as a smart contract platform. At the end of 2017, we proposed that blockchain should be regarded as the supporting infrastructure of tokens, which also caused extensive discussion in China and got a wide range of recognition.

Professor Jiaming Zhu, a renowned economist, believes that blockchain is one of the technologies with the rich applications and the profound impact in human history, so it is difficult to summarize it comprehensively, and it is not urgent to seek perfection in cognition. We highly agree with this point, and believe that all the definitions and descriptions of blockchain so far may be incomplete and just a glimpse into the eye. We are willing to combine the new thinking on asset expressions and further promote the understanding of blockchain along with tokens. In this section, we propose to understand blockchain as a contract supporting technology and the most important advance in this field since writing and paper.

Writing and paper, as a technology, has contributed to the promotion of human civilization probably more than all other technologies combined. There are two scenarios for the application of text and paper technology, one is to spread information, the other is to support contracts. Some people may think that contracts are also a kind of information, so there is maybe no difference between the two. But if you think about it carefully, you would come to different conclusions. Writing words on paper, duplicating them, advertising them, and spreading ideas and ideas are one thing, while recording agreements, forming consensus and even legal provisions, reserving evidence for future supervision and arbitration are a much different thing. In the former scenario, people pursue low-cost duplicating, editing and distribution, so typography is widely used. However, in the latter scenario, people’s demands are just the opposite. They pursue the authenticity, non-duplication, non-tampering and non-repudiation of contracts. They are afraid of forgery, let alone copying and editing. So far, handwritten signature and complex anti-counterfeiting printing technology are still widely used for authentication today.

Internet and blockchain are technological advances in these two scenarios respectively. The Internet is the digital upgrade of writing and paper technology in the scenario of information spreading, while the blockchain is the digital upgrade of writing and paper technology in the scenario of contract support, as exemplified in the figure below:

Two scenarios of text-paper technology and its digital evolution

Therefore, we describe blockchain (in one narrow form) as a distributed system maintained by many parties and supports the creation, verification, storage, circulation, execution and other related operations of digital contracts. The precursor technologies of blockchain are text contract, signature, standard contracts, bills, securities, currency notes andother contract technologies. The application of these technologies has a history of thousands of years, but the blockchain technology is the most important technological upgrade in this scenario in the last 1,000 years. Since contracts and laws are the basis of human institutions, blockchain has the potential impact to all institutional infrastructures.

In the previous section, we mentioned that we could express assets in a digital form before blockchain was invented. For example, contracts are digitalized with PDF documents, bills and tickets are digitalized with digital images, currencies are digitalized with digital points, and so on. We might as well call these technologies traditional contract digitization technologies. Then, what are the advantages of blockchain and token compared to them?

Comparing with blockchain, the traditional contract digitization technologies only scribbles the contracts and tickets that originally written on paper on to a screen, and do not realize full and major potential of the digital computing platform. On the other hand, the traditional contract digitization technologies introduce new weaknesses and even loopholes, which may cause severe consequences.

First, there are new security risks. Digital objects are vulnerable to be copied, tampered, and destroyed by unauthorized persons or hackers. Therefore, it is necessary to constantly check and enhance the security and reliability of the digital system. However, there are many potential security attack vectors, mandating rapid increases of computer security related expenditures.

Second, there are also trust and regulatory issues. In order to reduce the cost and risk of traditional contract digitization technology, a large amount of data and processes are concentrated in a few computing centers, and the important responsibility of maintaining the system is entrusted to a small number of technical professionals. This arrangement is low cost. But as the vast power is also concentrated in this small group of professionals, how to ensure their integrity and reliability, curb their impulse to use their monopoly position to extort the market, and how to effectively regulate or try to reduce the cost of supervision, has become a crucial and very difficult problem.

Thirdly, data privacy has become a hot topic as well. When based on a paper contract, both parties can fairly easily protect the data privacy of transactions and agreements physically. However, storing electronic contracts in a third-party centralized systems is no different from exposing the business secret to a trusteeship platform.

Fourth, it raises the problem of unfair data pricing. When a large amount of data, especially digital contracts, are centrally hosted on the third-party centralized platform, the centralized platform can obtain huge economic benefits through big data analysis, artificial intelligence and other algorithmic approaches. Whether the centralized platform will pay the data trustee for this, and how to price the managed data are all relevant questions. In fact, at present, the common phenomenon is that the centralized platform takes advantage of its strong position to carry out advantageous strategies in favor of itself.

How to improve the support and adoption of digital contract?

First of all, blockchain technology, with its time-sequentially, cryptographically linked list storage structure, greatly improves the consistency, tamper resistance, non-repudiation and reliability of contracts. This greatly reduces security risks and maintenance costs.

Secondly, the distributed and multi-party maintenance nature of blockchain infrastructure greatly improves the transparency, reliability, and decentralization of data storage and reduces the trust risk and regulatory cost.

Third, the universal and ubiquitous cryptographic applications of blockchain provide rich appoarches and possibilities for data privacy protection.

Fourth, blockchain can effectively package and express data assets, transparently display their transactions, and find their fair prices for transactions through the market.

Fifth, the smart contract in blockchain can express the contract terms through code and can execute it automatically when the condition is triggered. Thus, the contract execution, which originally needs to be done by human, is now done by the computer, which greatly reduces the cost of contract execution.

Based on the characteristics above, we can say that blockchain is the first technology that can effectively support contract digitalization after the generation of computers and networks. The digitalization of contracts can only be fully realized after the emergence of blockchain. There is no comparison with the previous traditional contract digital technology — we have stepped up to a new level.

Because blockchain itself is a platform of digital contracts, and a contract is the basic expression of assets, blockchain has become an ideal infrastructure for digital expression of assets, that is, digital assets.

5. Digital expression of assets in blockchain

So far, digital assets mainly exist in the form of fungible tokens. Starting with Bitcoin, most digital assets in blockchain and open finance are designed as homogeneous certificates. In the Ethereum ecosystem, this kind of homogeneous certificate is often created according to the ERC-20 standard. According to our statistics, by the end of September 2020, there were 297,000 ERC-20 smart contracts deployed on the main chain of Ethereum, while less than 6,500 smart contracts were to create heterogeneous, “Non-fungible tokens”, or NFTs.

But in fact, according to the previous discussion, smart contracts can be the most basic form of digital assets.

Ethereum supports a Turing-complete virtual machine with smart contracts, rendering it a general digital contract management platform. In other words, the blockchain has the ability to express general, non-standard contracts. That’s it — a smart contract itself can be digital assets. Of course, compared with natural language, its expression ability is far from sufficient, but it can solve many simple, practical problems. Moreover, since the blockchain can digitally express general contracts, it can also digitally express standard contracts, bills, securities and currencies.

We show the corresponding technologies as follows:

At present, the blockchain has effectively supported a variety of expressions for assets:

The general arbitrary, non-standard contracts are implemented as general smart contracts on a blockchain.

Standard contracts are also implemented by smart contracts. Some contract templates and libraries help simplify the work.

Bills as an asset-expression technology have rich and wide applications. At present, there is no parallel implementation on blockchains, the closest is non-fungible token (NFT), but NFT is far from covering the rich use cases of bills. Despite that, there is no technical barrier to mimic bills in blockchains, and several efforts have been reported.

Securities and currency can be supported with tokens and native cryptocurrencies on blockchains. This was, in fact, the first application of blockchain.

Thus, blockchain has the ability to support all major forms of digital assets, and has brought great technical advantages for the designing, creating, management and application of digital assets, and has become THE supporting platform of digital assets.

6. Technical discussion

So far, we have expressed our main views on digital assets in the form of text description. Readers with experience in object-oriented programming may have noticed that the relationship of five types of digital assets (contracts, standard contracts, bills, securities and currencies) in this article constitutes a typical class inheritance graph.

Therefore, the last part of this article discusses how to define the five types of digital assets above through code.

In fact, using code to define digital assets is not only for the sake of concise and accurate description but also has great practical value. It must be stated that we are still studying this subject and there are still issues remained to be solved. Only the general ideas are put forward for reference.

When defining digital assets by code, there will be a series of new problems and challenges. Natural language can be vague and general description, and the code must be clear, accurate and unambiguous. Therefore, how to reflect some of the ideas expressed in natural language in the previous sections has become a great challenge.

For example, when defining assets, we mentioned that assets are expected to bring economic benefits. This sentence is easy to say, but how to express it as code? In other words, how to use code to show that something has expected benefits? It seems impossible. However, as we mentioned in the extended discussion on this issue in the first section, the direct inference that assets have expected returns is that assets must have income distribution arrangements, that is, income distribution rules must be arranged in advance. Therefore, we believe that the way to express “assets have expected return” in the code is to arrange a method of performing an income distribution transfer with the function: allocate_ benefit().

The following will not elaborate on the theoretical issues, but directly describe several major types of digital assets through Python-like pseudo-code.

# General digital assets
class DigitalAsset:
    def get_contract()
    def get_controller()
    def allocate_benefit()# Standard contracts
class ContractTemplate:
    passclass StandardContract(DigitalAsset):
    def get_contract_template()
    def make() # create contract# Bills
class Bill(StandardContract):
    def print()
    def get_rules()
    def run_rule()# Securities and cryptocurrencies are implemented as tokens
class Token:
    pass # please refer to the ERC-20 standard

7. Summary

This paper discusses topics ranging from the definition of assets to the expression and classification of digital assets, then digital assets on blockchains. First, we define assets as a collection of rights formed and adjusted by transactions or other contractual acts, with clear owners or controllers, and expected to bring economic benefits. Then, we point out that contracts are the most common form of expression of assets, while standard contract, bills, securities and currencies are all contract expressions, listed by an increasing degree of standardization. For digital assets, this article defines them as the digital expression of assets. Corresponding to the five expressions of assets, blockchain provides strong supporting capabilities, rendering itself the ideal platform of digital assets in the 21st century.


  • Wang, Zejian, General Principles of Civil Law
  • Order №76 of the Ministry of Finance of the People’s Republic of China, Accounting Standards for Business Enterprises
  • David Graeber, Debt: The first 5,000 years
  • Zhou Z., Account, Social Sciences Literature Press, 2017
  • Yuan, D., Meng, Y., Token are the Key to the Next Generation of Internet Digital Economy, https://blog.csdn.net/myan/article/details/78712506
  • Zhu J., The Future Decides the Present: Blockchain, Digital Currency and Digital Economy, Shanxi People’s Publishing House, 2020

Acknowledgement: related research work involved in this paper was carried out at the request of Professor Zhu Jiaming, chairman of Academic and Technical Committee of Chinese Institute of Digital Assets (CIDA), and was guided and reviewed by Professor Zhu. Mr Qing Shao, vice president of CIDA, also reviewed this article and put forward valuable opinions. Thanks to their help and participation.

About us:

Unizon is a development team, dedicated to blockchain and open financial technology, and specializing in DeFi protocol development, technical advisory services, and model design for Tokenomics.


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