The accusation usually lands within days of bid opening: the losing rival claims two bids in the package were “green army, red army” — one genuine bidder and one planted companion bid. For the accused contractor, what happens in the first days decides almost everything, because collusive bidding is among the most heavily sanctioned prohibitions in Bidding Law No. 22/2023/QH15, and the line between “unfairly suspected” and “proven to have agreed” is drawn by evidence, not by denials.
What the law calls this conduct, and what must be proven
Clause 3, Article 16 of the 2023 Bidding Law defines bid-rigging through three behaviours. Point (a) covers arranging, agreeing or coercing so that one or several parties prepare bids or withdraw bids in order for one party to win. Point (b) covers arranging or agreeing to refuse to supply goods or services, to refuse a subcontract, or using other arrangements to restrict competition so one party wins. Point (c) covers a capable, experienced bidder that has bid and met the invitation requirements but deliberately withholds capability documents when asked to clarify or verify, in order to let another party win. The core element in all three is agreement or arrangement; two bidders coincidentally pricing close, buying materials from the same distributor, or using the same estimating consultant does not by itself constitute rigging.
Investigations in practice start from surface indicators: two bids sharing a rare typo, the same IP address or computer submitting on the National Bidding Network System, bid bonds issued by the same bank in consecutive serial numbers, the companion bid priced higher by a regular margin, or staff who moved between the two firms. These indicators justify an inspection; they are not yet proof of agreement. The accused bidder’s task in every submission is to separate the two layers: acknowledge what is factually true and explainable by ordinary business relations, while requiring the accuser and the handling authority to identify the evidence of the agreement element.
Consequences, layer by layer
The first layer sits inside the package itself: under Points (d) and (dd), Clause 1, Article 17 of the 2023 Bidding Law, a winning bidder committing a prohibited act — or another organisation or individual doing so in a way that distorts the selection result — is a ground for bid cancellation. The second layer is debarment under Article 125 of Decree 24/2024/ND-CP: a Point (a), Clause 3, Article 16 violation draws a ban of 03 to 05 years; Points (b) or (c) draw 01 to 03 years; the limitation period for imposing a ban is 10 years from the violation. For a consortium bidder, the ban by default covers every member, save for statutory cases where only the violating member is banned. The third layer is criminal: bid-rigging causing serious consequences may be prosecuted under Article 222 of the 2015 Penal Code for violating bidding regulations causing serious consequences. The three layers run independently; surviving the in-procedure petition layer does not erase exposure in the other two.
A practical response path for the first 30 days
Step one is to freeze evidence in your own favour: preserve the entire bid-preparation trail — source files with metadata, internal pricing history, supplier quotations, correspondence — and never edit or delete anything, because destroying or concealing evidence is itself a prohibited obstruction act under Clause 5, Article 16. Step two is a written explanation to the project owner and the bid solicitor focused on your independent pricing process: who priced the bid, on which quotations, and why technical overlaps with the rival bid flow from the shared electronic bidding documents or a common supplier. Step three, if an adverse decision is issued during selection, is the petition mechanism in Articles 89, 90 and 91 of the 2023 Bidding Law, in parallel with preparing a complaint or administrative lawsuit against any debarment decision.
Step four is communications discipline: a single spokesperson, and no contact with the suspected companion bidder to “align stories” — that contact itself manufactures exactly the agreement evidence the other side is looking for. If criminal-investigation signals appear (an invitation to work on Article 222 of the Penal Code), criminal counsel must join from the first session, kept separate from the bidding-petition team.
Frequently Asked Questions
What must be proven for a cover-bidding accusation to stand?
The legal basis is Clause 3, Article 16 of the 2023 Bidding Law, and the element that must be proven is arrangement or agreement. Surface signs — a shared submission IP address, identical typos, bonds from the same bank — justify inspection only; a rigging conclusion needs further evidence such as communications, work-sharing arrangements or money flows between the bidders.
How long is the debarment for bid-rigging?
Under Article 125 of Decree 24/2024/ND-CP, arranging bid preparation or withdrawal under Point (a), Clause 3, Article 16 is banned for 03 to 05 years, while Points (b) and (c) conduct draws 01 to 03 years. The limitation period for imposing the ban is 10 years from the date of the violation.
Can bid-rigging lead to criminal liability?
Yes, potentially. Article 222 of the 2015 Penal Code criminalises violating bidding regulations causing serious consequences, and bid-rigging is among the listed behaviours. Prosecution turns on the scale of consequences and proof of agreement; being accused, or even having a bid cancelled, does not by itself mean criminal prosecution.
Where does a wrongly accused bidder complain first?
First, explanation and petition inside the selection procedure itself under Articles 89 to 91 of the 2023 Bidding Law, addressed to the project owner, the bid solicitor and the competent person. If a debarment decision is then issued, the bidder complains against that decision under the 2011 Law on Complaints or brings an administrative case in court.
This article has been quality-reviewed by the FLAW AI Legal Council