Architecture Board (AB) is one of three Plenary Bodies chartered by the Object Management Group® (OMG) Board of Directors (BoD). The AB is composed of the Architecture Board Chair and ten elected member representatives, five elected by the Domain Technology Committee (DTC), the other five by the Platform Technology Committee (PTC). The AB must certify every Request For Proposal (RFP) before it may be issued, and every specification before it may be adopted; the AB also charters some Special Interest Groups (SIGs) and Subcommittees(SCs), but may not charter Task Forces (TFs).
Source: https://www.omg.org/gettingstarted/terms_and_acronyms.htm#ab