Mark Friedenbach

Author of 6 BIPs.

BIP 68: Relative lock-time using consensus-enforced sequence numbers: Deployed. Gives transactions a "relative lock-time," so a coin cannot be spent until a set number of blocks or amount of time has passed since it was confirmed. This is an essential building block for payment…
BIP 98: Fast Merkle Trees: Draft. Specifies a faster and safer version of the Merkle tree, the data structure Bitcoin uses to summarize many items in one fingerprint so that any single item can be proven to be included. The design…
BIP 112: CHECKSEQUENCEVERIFY: Deployed. Introduces CHECKSEQUENCEVERIFY, a script instruction that lets coins be locked until a certain amount of time has passed since they were received. This 'relative timelock' is a key building block…
BIP 113: Median time-past as endpoint for lock-time calculations: Deployed. Changes how Bitcoin measures time for timelocked transactions, using the median time of the previous 11 blocks instead of a single block's timestamp. Because this value only moves forward, miners…
BIP 116: MERKLEBRANCHVERIFY: Draft. Proposed MERKLEBRANCHVERIFY, a script instruction that checks whether a piece of data belongs to a committed set using a Merkle proof. It would let complex contracts reveal only the spending…
BIP 117: Tail Call Execution Semantics: Draft. Proposed letting a script hand off execution to another script supplied at spending time, a 'tail call'. Combined with BIP 116, this would allow contracts with many possible spending conditions…