§ 16.2the blackletter · sectionp. 18

§ 16.2  Identification of Parties and Liable Entities; the Coldiron Disclosures

● settled · en banc · quotations verified 8/24/26 · cite: Blackletter § 16.2, p. 18 (2026) ·
“Read together, WCAB Rules 10390, 10400 and 10401 ensure that all parties, representatives and liable entities are fully identified in each case.”

(DiFusco, supra, at p. 12.)

“Under WCAB Rule 10390, which renumbered and simplified former WCAB Rule 10550, all parties must fully disclose their own legal name, the name of their attorney or non-attorney representative, the name of the insurer and employer, and the third-party administrator, while clarifying that the third-party administrator is not a party.”

(DiFusco, supra, at p. 12.)

“WCAB Rule 10400, subdivision (b)(1) requires that all attorney representatives file a notice of representation or opening document that complies with WCAB Rule 10390 and includes “the name of the represented party.””

(DiFusco, supra, at p. 12, citing Cal. Code Regs., tit. 8, § 10400(b)(1).)

“As a matter of course, if an attorney represents multiple parties or entities, all names of each represented party or entity must be disclosed. WCAB Rule 10401 imposes similar requirements on non-attorney representatives.”

(DiFusco, supra, at p. 12, citing Cal. Code Regs., tit. 8, § 10401.)

“[W]here an employer’s liability for workers’ compensation benefits is adjusted by a third-party administrator, the administrator must disclose to the Workers’ Compensation Appeals Board, to the other parties in any proceeding in which it is a party, and to its own counsel the identity of its client, whether a self-insured employer or insurance carrier. If the client is an insurance carrier, the administrator must disclose whether the policy includes a “high self-insured retention,” a large deductible, or any other provision that affects the identity of the entity actually liable for the payment of compensation. Failure of the administrator to disclose the identity of its client may subject it to sanctions pursuant to Labor Code section 5813.”

(Coldiron v. Compuware Corp. (2002) 67 Cal.Comp.Cases 289, 290–291 (Appeals Bd. en banc) [Coldiron I], as quoted in DiFusco, supra, at p. 8.)

“Fundamental to the establishment of workers’ compensation liability and the prompt delivery of benefits awarded to eligible injured workers is the designation of the responsible and liable entity. The responsible entity must be divulged at the earliest opportunity, and certainly no later than the commencement of the litigation process and formal proceedings. . . . In this manner, no confusion can result as to the liable entity, against whom an award for benefits will be made. It avoids unnecessary delays in the prompt delivery of benefits awarded.”

(Coldiron I, supra, 67 Cal.Comp.Cases at p. 294 (Appeals Bd. en banc), as quoted in DiFusco, supra, at p. 10.)

HOLDING No. 3 · DIFUSCO (2025) · EN BANC · BINDING · at p. 2
“WCAB Rule 10390 does not supersede the Coldiron decisions. Defendants must comply with WCAB Rule 10390 and the disclosure requirements in Coldiron I and II, regardless of whether there is a third-party administrator.”
“[T]here is no basis to limit the disclosure requirements to third-party administrators.”

(DiFusco, supra, at p. 10.)

“It bears repeating that the Appeals Board, in issuing Coldiron I en banc was concerned with disclosure of the entity responsible for payment in all cases, including any limits on liability for payment, and not just those with a third-party administrator.”

(DiFusco, supra, at p. 10.)

“The burden to ascertain the identity of the entity liable for payment cannot be placed on the injured worker; the information is more readily available to a defendant, and the disclosure responsibility must lie with defendant.”

(DiFusco, supra, at p. 10.)

“We observe that information as to the proper defendant is within a defendant’s control, and not an applicant’s, so that it is incumbent upon a defendant to comply with this responsibility.”

(DiFusco, supra, at p. 12.)

“As outlined in Coldiron, and as further required by these rules, full disclosure of the names of each party or entity means that all essential parties are included in all awards, and so that awards are enforceable, a defendant must necessarily provide accurate information.”

(DiFusco, supra, at p. 12, citing Lab. Code, §§ 5806, 5807.)

“Defendants are required by the Labor Code to pay all compensation that is due. If a dispute arises about who is responsible to pay compensation, an identified defendant may nevertheless be held liable, and sanctions may be imposed until such time as another responsible party is identified.”

(DiFusco, supra, at p. 14.)

“[t]hese holdings remain in full force and effect, and the third-party administrators (or their counsel and/or representative) who do not comply with these holdings may be subject to sanctions.”

(Coldiron v. Compuware Corp. (2002) 67 Cal.Comp.Cases 1466, 1470 (Appeals Bd. en banc) [Coldiron II], as quoted in DiFusco, supra, at p. 9.)

“The WCJ has a duty to inquire and ensure that the record reflects the correct identity of all parties, at first opportunity, including at the mandatory settlement conference and at trial.”

(DiFusco, supra, at p. 14.)

“[T]he WCJ must exercise oversight to ensure that at the time an award or decision is issued, if applicant has sought this information, that defendant has disclosed and properly identified all liable entities and the relevant insurance policy details, in compliance with Coldiron I and this decision.”

(DiFusco, supra, at p. 14.)

“WCJs are nevertheless responsible for ensuring that the legally correct names of parties and liable entities appear in case captions, rather than shortened or otherwise incorrect names found in EAMS.”

(DiFusco, supra, at p. 14, fn. 11.)

“[L]ien claimants and applicants are similarly entitled to this information, and similarly unable to access it without disclosure by the defendant.”

(DiFusco, supra, at p. 11, fn. 7.)

Cross-references: § 1.2 (why Coldiron still binds); § 17.1 (the discovery route to the same information); § 22.1 (policy provisions affecting liability); § 14.9 (sanctions generally).

← § 14.9 · § 16.3 → · this section in the book

California Workers’ Compensation Blackletter (2026)18