Two ASN 99s

This is probably a really stupid question, but why are there two ASN
    99s? Was ASN 99 recycled or reassigned or something?
    I did a really quick uniq through the ASN list, and the only other
    duplicate registrations I see are more-specifics for ASNs which were
    assigned in blocks, 1381 and 3933, for example, but this doesn't seem
    to be such a case.

    Intel Corporation (ASN-INTEL) 99
    University of Maryland (ASN-00) 99
    Advanced Networks & Services Inc. (ASN-ANSBB-ASNNET-2-ASNBLOCK) 1381
    Merit Computer Network Incorporated (ASN-NSFNETTEST46) 1381
    NorthWestNet (ASN-NWNET-ASBLK1-ASNBLOCK) 3933
    Oregon Department of Education (ASN-OPEN-NORTH) 3933