Article II. Civil Practice · Part 6. Pleading · Last amended 1995 · Last verified July 20, 2026
In one sentenceA plaintiff in an Illinois product-liability action seeking harm damages must file an affidavit -- backed by a qualified expert's written report meeting specific content requirements -- certifying a reasonable and meritorious basis for the claim, mirroring the malpractice screening in 2-622.
Full Text of 735 ILCS 5/2-623
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(a)In a product liability action, as defined in Section 2-
2101, in which the plaintiff seeks damages for harm, the plaintiff's attorney or the plaintiff, if the plaintiff is proceeding pro se, shall file an affidavit, attached to the original and all copies of the complaint, declaring one of the following: (1) That the affiant has consulted and reviewed the
facts of the case with a qualified expert, as defined in subsection (c), who has completed a written report, after examination of the product or a review of literature pertaining to the product, in accordance with the following requirements:
(A) In an action based on strict liability in tort or implied warranty, the report must:
(i)identify specific defects in the product that have a potential for harm beyond that which would be objectively contemplated by the ordinary user of the product; and
(ii)contain a determination that the product was unreasonably dangerous and in a defective condition when it left the control of the manufacturer. (B) In any other product liability action, the report must identify the specific act or omission or other fault, as defined in Section 2-1116, on the part of the defendant. (C) In any product liability action, the report must contain a determination that the defective condition of the product or other fault was a proximate cause of the plaintiff's harm. (2) That the plaintiff has not previously voluntarily dismissed an action based upon the same or substantially the same acts, omissions, or occurrences and that the affiant was unable to obtain a consultation required by paragraph (1) because either a statute of limitations would impair the action and the consultation required could not be obtained before the expiration of the statute of limitations or despite a good faith effort to comply with this Section, the plaintiff was prevented by another person from inspecting or conducting nondestructive testing of the product. If an affidavit is executed pursuant to this paragraph, the affidavit required by paragraph (1) shall be filed within 90 days after the filing of the complaint. The defendant shall be excused from answering or otherwise pleading until 30 days after being served with an affidavit required by paragraph (1). No plaintiff shall be afforded the 90-day extension of time provided by this paragraph (2) if he or she has voluntarily dismissed an action for the same harm against the same defendant. (b) When the defective condition referred to in the written report required under paragraph (1) of subsection (a) is based on a design defect, the affiant shall further state that the qualified expert, as defined in subsection (c), has identified in the written report required under subsection (a) either: (i) a feasible alternative design that existed at the time the product left the manufacturer's control; or (ii) an applicable government or industry standard to which the product did not conform. (c) A qualified expert, for the purposes of subsections (a) and (b), is someone who possesses scientific, technical, or other specialized knowledge regarding the product at issue or similar products and who is qualified to prepare the report required by subsections (a) and (b). (d) A copy of the written report required by subsections (a) and (b) shall be attached to the original and all copies of the complaint. The report shall include the name and address of the expert. (e) The failure to file an affidavit required by subsections (a) and (b) shall be grounds for dismissal under Section 2-619. (f) Any related allegations concerning healing art malpractice must include an affidavit under Section 2-622. (g) This amendatory Act of 1995 applies only to causes of action filed on or after its effective date.
Plain-English Summary
Section 2-623 extends the certificate-of-merit screening approach of 2-622 into product-liability litigation. Subsection (a) requires the plaintiff's attorney, or a pro se plaintiff, to file an affidavit with the complaint, generally supported by a written report from a qualified expert who examined the product or reviewed relevant literature. For a strict-liability or implied-warranty claim, the report must identify specific defects creating potential harm beyond what an ordinary user would expect, and conclude the product was unreasonably dangerous and defective when it left the manufacturer's control; for any other product-liability theory, it must identify the specific act, omission, or other fault under Section 2-1116; and in every case, it must find that the defect or fault proximately caused the plaintiff's harm.
Paragraph (2) gives a plaintiff who couldn't get that consultation in time -- because the limitations period would run, or because someone blocked inspection or testing of the product despite a good-faith effort -- 90 days after filing the complaint to submit the affidavit, with the defendant excused from answering until 30 days after being served with it. That extension isn't available to a plaintiff who has already voluntarily dismissed a prior action for the same harm against the same defendant.
Subsection (b) adds a requirement specific to design-defect claims: the qualified expert's report must identify either a feasible alternative design that existed when the product left the manufacturer's control, or an applicable government or industry standard the product failed to meet. Subsections (c) through (d) define the qualified expert and the filing requirements, and subsection (e) makes the failure to file the required affidavit grounds for dismissal under Section 2-619 -- the same consequence 2-622 attaches to a missing malpractice certificate. Subsection (f) requires a separate 2-622 affidavit for any related healing-art malpractice allegations, and subsection (g) applies the section only to causes of action filed on or after its 1995 effective date.
Frequently Asked Questions
What must a plaintiff file to bring a product-liability action for harm damages?
An affidavit under 2-623(a), generally supported by a qualified expert's written report meeting the content requirements the section spells out for the specific theory of liability pleaded.
What must the expert's report say in a strict-liability or implied-warranty claim?
It must identify specific defects with potential for harm beyond what an ordinary user would expect, and conclude the product was unreasonably dangerous and defective when it left the manufacturer's control.
What if the claim involves a design defect specifically?
Subsection (b) requires the report to identify either a feasible alternative design that existed when the product left the manufacturer's control, or an applicable government or industry standard the product didn't meet.
Can a plaintiff delay filing the affidavit?
Yes, under paragraph (2), if the limitations period would otherwise run or someone blocked inspection or testing of the product despite good-faith efforts -- the affidavit then follows within 90 days of the complaint, unless the plaintiff already voluntarily dismissed a prior action for the same harm against the same defendant.
What happens if the required affidavit is never filed?
Subsection (e) makes that failure grounds for dismissal under Section 2-619, the same consequence that applies to a missing malpractice certificate under 2-622.
Amendment History
(Source: P.A. 89-7, eff. 3-9-95.)
Source & verification. Section text and amendment history are
reproduced verbatim from the Illinois Compiled Statutes, published by the
Illinois Compiled Statutes, Illinois General Assembly / Legislative Reference Bureau. Last verified July 20, 2026.
· Official source
Also known as:certificate of merit illinois product liabilityqualified expert affidavit illinoisdesign defect affidavit illinois