Summary: A letter from a prospective contractor accusing the Federal Aviation Administration (FAA), Eastern Region, of "bid rigging" in two procurements was forwarded to GAO. In both procurements, FAA canceled advertised bid solicitations after bid opening due to what it considered excessive bid prices. After various requests for the submission of prices on a negotiation basis, award was made in both procurements to firms other than the protester. The protester filed protests of both contract awards, contending that numerous requests for the submission of price offers by FAA constituted "bid rigging." Although the protester knew of the requests for the submission of prices on a negotiation basis by early August, 1979, at the latest, in one instance and by at least September 21, 1979, in the other instance, the protests were not received by GAO until October 31, 1979. Protests must be filed within 10 working days after the basis is known or should have been known. No untimely protest will be considered on its merits unless good cause for consideration is shown or where issues significant to procurement practices or procedures exist. It did not appear that either of these conditions was present in the instant cases.