As provided in 814.201-6(a), the following provision will be included in all invitations for bid:
CAUTION TO BIDDERS - BID ENVELOPES (JAN 2008)
It is the responsibility of each bidder to take all necessary precautions, including the use of proper mailing cover, to insure that the bid price cannot be ascertained by anyone prior to bid opening. If a bid envelope is furnished with this invitation, the bidder is requested to use this envelope in submitting the bid. The bidder may, however, use any suitable envelope, identified by the invitation number and bid opening time and date. If an Optional Form (OF) 17, Sealed Bid Label, is furnished with this invitation in lieu of a bid envelope, the bidder is advised to complete and affix the OF 17 to the lower left corner of the envelope used in submitting the bid.
(End of Provision)