FAR and DFARS › FAR Part 15: Contracting by Negotiation › Subpart 15.6
FAR 15.608 Prohibitions.
The codified text (eCFR, as of 2026-10-02). Under the Revolutionary FAR Overhaul ↗, agencies follow class deviations with new text for many parts while the formal rules go through the Federal Register: check the solicitation and your contract's clauses, which rule.
In plain English
This section bars government personnel from using any part of an unsolicited proposal as a basis for a solicitation or negotiations with another firm unless the offeror is notified and agrees. It also bars disclosing restrictively marked information in an unsolicited proposal, with possible criminal penalties for disclosing trade secrets and similar matters. For contractors, it protects the ideas and marked data they submit without being asked.
Applies to: Government personnel handling unsolicited proposals
What it requires
- Notify the offeror and obtain agreement before using any data, concept, idea, or other part of an unsolicited proposal as a basis for a solicitation or negotiations with another firm
- Do not disclose restrictively marked information included in an unsolicited proposal
Key terms: unsolicited proposal · restrictively marked information · trade secrets · solicitation · offeror
Written by AI from this section's text. A guide, not legal advice: the text below rules.
The text
(a) Government personnel shall not use any data, concept, idea, or other part of an unsolicited proposal as the basis, or part of the basis, for a solicitation or in negotiations with any other firm unless the offeror is notified of and agrees to the intended use. However, this prohibition does not preclude using any data, concept, or idea in the proposal that also is available from another source without restriction.
(b) Government personnel shall not disclose restrictively marked information (see 3.104 and 15.609) included in an unsolicited proposal. The disclosure of such information concerning trade secrets, processes, operations, style of work, apparatus, and other matters, except as authorized by law, may result in criminal penalties under 18 U.S.C. 1905.
← 15.607 Criteria for acceptance and negotiation of an unsolicited proposal. · 15.609 Limited use of data. →
Rule changes for FAR Part 15
- Federal Acquisition Regulation: Revolutionary FAR Overhaul Parts 8, 12, 13, 15, 38, 44, and 51 ↗ · proposed 2026-09-18 · comments due 2026-10-19
- Federal Acquisition Regulation: Inflation Adjustment of Acquisition-Related Thresholds ↗ · final rule 2025-08-27 · effective 2025-10-01
- Federal Acquisition Regulation: Preventing Organizational Conflicts of Interest in Federal Acquisition ↗ · proposed 2025-01-15 · comments due 2025-03-17
- Federal Acquisition Regulation: Controlled Unclassified Information ↗ · proposed 2025-01-15 · comments due 2025-03-17
- Federal Acquisition Regulation: Inflation Adjustment of Acquisition-Related Thresholds ↗ · proposed 2024-11-29 · comments due 2025-01-28
- Federal Acquisition Regulation: Reverse Auction Guidance ↗ · final rule 2024-07-30 · effective 2024-08-29
- Federal Acquisition Regulation: Sustainable Procurement ↗ · final rule 2024-04-22 · effective 2024-05-22
Source: eCFR, 48 CFR chapters 1 and 2 (GPO GovInfo bulk data) ↗. Plain words for the terms: glossary.