To conclude discussion on BIP 2, I have opened a pull request to implement it
and mark it active. Note this implies activation and implementation of BIP 123
as well: https://github.com/bitcoin/bips/pull/478

I plan to merge this on December 14th. If there are any hard objections to
this change, please bring it up on the bitcoin-dev mailing list before then.
Further reviews of the implementation are welcome in the meantime. Please
refrain from requesting further changes to the BIPs themselves unless it is a
blocker/show-stopper or trivial (not changing the meaning).

In the process of implementing BIP 2, I came across a number of BIPs which
managed to get into the repository without a proper license. Authors of any of
these BIPs should open a pull request adding the necessary Copyright section
and License header(s). (If there are other contributors to the document in the
BIP git logs, I will try to reach out to them to get permission. If you have
accepted contributions from anyone not documented in git as an Author, please
mention this in the PR explicitly.)

These BIPs need a license:
 001  BIP Purpose and Guidelines
 010  Multi-Sig Transaction Distribution
 011  M-of-N Standard Transactions
 012  OP_EVAL
 013  Address Format for pay-to-script-hash
 014  Protocol Version and User Agent
 015  Aliases
 016  Pay to Script Hash
 021  URI Scheme
 030  Duplicate transactions
 031  Pong message
 032  Hierarchical Deterministic Wallets
 033  Stratized Nodes
 034  Block v2, Height in Coinbase
 035  mempool message
 039  Mnemonic code for generating deterministic keys
 043  Purpose Field for Deterministic Wallets
 044  Multi-Account Hierarchy for Deterministic Wallets
 045  Structure for Deterministic P2SH Multisignature Wallets
 047  Reusable Payment Codes for Hierarchical Deterministic Wallets
 061  Reject P2P message
 062  Dealing with malleability
 064  getutxo message
 066  Strict DER signatures
 067  Deterministic Pay-to-script-hash multi-signature addresses through
          public key sorting
 068  Relative lock-time using consensus-enforced sequence numbers
 070  Payment Protocol
 071  Payment Protocol MIME types
 072  bitcoin: uri extensions for Payment Protocol
 073  Use "Accept" header for response type negotiation with Payment Request
          URLs
 075  Out of Band Address Exchange using Payment Protocol Encryption
 101  Increase maximum block size
 102  Block size increase to 2MB
 103  Block size following technological growth
 106  Dynamically Controlled Bitcoin Block Size Max Cap
 120  Proof of Payment
 121  Proof of Payment URI scheme
 123  BIP Classification

Thanks,

Luke