Lesson 4: Divulgence & Transaction Projection

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1. 0:00

   this lesson further explores the concept of divulgence where non- stakeholders gain visibility into contracts fetched from a choice transaction projection elucidates each party's distinct perspective facilitating a better understanding of contract disclosure divulgence occurs when non- stakeholders gain visibility into contracts that are fetched as a result of exercising a choice a contract may also become

2. 0:34

   visible to non- stakeholders as it is created as a result of exercising a choice in the previous lesson you were able to confirm that Bob's asset contract of $100 and the total asset amount of $130 became visible to Alice by analyzing the transaction trees now let's walk through the table view in the table view US Bank issues $11,000 from which $400 is offered to Alice creating a new $600 asset for US Bank from the remaining

3. 1:12

   $600 US Bank offers $100 to Bob which he accepts at this point Alice has $400 US Bank has $500 and Bob has $100 Alice offers $3 to Bob out of her $400 creating a new $370 asset contract for herself as Bob accepts the $30 from Alice his existing total amount of asset $100 is archived and a new asset of $130 is created when Bob accepts the $30 from Alice as his existing asset $100 is fetched in the process of creating a new asset

4. 2:01

   $130 both his fetched asset and his new asset become visible to Alice indeed the $100 that Bob has accepted from UB has been marked D for Alice which indicates that the particular asset owned by Bob has been divulged to Alice on the other hand in the last row which shows Bob's total account balance of $130 Alice is marked w which stands for witness as you know the S stands for

5. 2:34

   signatory of the contract and O stands for Observer for the contract the D indicates that the contract has been divulged to a non- stakeholder such as Alice because they witnessed an exercise that resulted in a fetch of this contract in other words when Bob exercised the asset transfer proposal accept choice on the contract where Alice and UB are signatories the $100 asset contract was

6. 3:06

   fetched in the body of the choice on the $100 asset UB is still an issuer one of the signatories but Alice is not a stakeholder of the fetched contract in any way therefore the contract is considered to have been divulged to Alice on the other hand the w means a party witnessed the action that created the contract contct but they're not a stakeholder of the contract that is created as a result of the action

7. 3:36

   therefore they remain informed as parties who witnessed the contract hence the W in other words Alice can view the accept Choice exercised by Bob since the choice was exercised on the proposal contract where Alice is one of the signatories however Alice is not one of the stakeholders of the contract that's been newly created created as a result of the exercise action it is important to note that both D and W indicate that the contract became visible to non-

8. 4:17

   stakeholders stakeholders should see changes to contracts they hold a stake in but that does not mean that they have to see the entirety of any transaction that their contract is involved in this is made precise through projections of a transaction which Define The View that each party gets on a transaction given a transaction a party should see the subtransaction consisting of all actions on contracts where the party is a

9. 4:48

   stakeholder thus privacy is obtained on the subtransaction level projecting The Ledger of the asset transaction workflow example yields the following projections for for Alice and Bob when Alice decides to offer $30 to Bob her asset contract with the value of $400 is archived a new asset contract is created with the New Balance which is her transferring amount subtracted from her original total balance which is

10. 5:22

    $370 neither archival nor creation of these asset contracts is visible to Bob since he is not a stakeholder on those contracts when Alice the original owner of the transferring asset creates an asset transfer proposal contract with Bob as the receiver the contract becomes visible not only to Alice but also to Bob since the receiver is an observer on the contract and the creation of the contract is a state-changing action which is visible to the

11. 5:55

    Observer when Bob decides to accept the asset transfer proposal from Alice his existing asset contract issued by US Bank is fetched Bob's existing asset balance $100 is combined with the transferred amount $30 and a new asset contract is created with the new total balance $130 since Bob exercises the accept choice on the proposal contract on which both Alice and US Bank are stakeholders all the consequences of the exercise action such as Fetch and create become visible to all three of Alice Bob

12. 6:37

    and the US Bank this lesson focused on the concept of divulgence which occurs when a non- stakeholder gains visibility into contracts that are fetched as a consequence of a choice being exercised a contract may also become visible to non- stakeholders as it is created as a result of exercising a choice in the table view of a transaction D indicates that the contract has been divulged to a particular party that

13. 7:07

    witnessed an exercise that resulted in a fetch of the contract while W indicates that the party sees the contract created for example from an exercise of which they were the actor both cases indicate that the contract became visible to non- stakeholders additionally transaction projection represents the unique view obtained by each party within a transaction it ensures that a party observes only the subtransaction containing actions where the party is

14. 7:39

    informed this AIDS in understanding how contracts are disclosed and enhances comprehension of the perspective held by each party involved