As the Legislature printed it
DIVISION 4. WORKERS' COMPENSATION AND INSURANCE [3200 - 6002] · PART 2. COMPUTATION OF COMPENSATION [4451 - 4856] · CHAPTER 2. Compensation Schedules [4550 - 4856] · ARTICLE 2. Medical and Hospital Treatment [4600 - 4615]
How panels applied this section
Newest released decisions whose legal-standard extraction named this section. Each quotes the passage and links to the official PDF. Unofficial guide — not legal advice.
- ADJ11775583 · 2026-09-23 · Van Nuys District Office§ 4604
Determinative passage · p.6Section 5304 states in pertinent part that “[t]he appeals board has jurisdiction over any controversy relating to or arising out of Sections 4600 to 4605….” (Lab. Code, § 5304; see §§ 5300, 5301.) Section 4604 provides that “[c]ontroversies between employer and employee arising under this chapter shall be determined by the appeals board, upon the request of either party, except as otherwise provided by Section 4610.5.” (Lab. Code, § 4604.) Pursuant to section 4610.5, IMR is the exclusive remedy for an employee challenging a valid, timely UR determination. (Lab. Code, § 4610.5(a).) Section 4610.5 provides for review of disputes by IMR when UR has modified or denied the medical treatment request as not medically necessary. UR decisions validly obtained in compliance with section 4610 will trigger the IMR process of section 4610.5, in which case jurisdiction over the controversy rests solely with the IMR process. In contrast, when the underlying UR decision is not validly obtained or is not timely pursuant to section 4610, there is no basis upon which to trigger the IMR process of section 4610.5.
The WCAB has jurisdiction over medical treatment disputes unless a valid UR decision triggers the IMR process; here, the March 16, 2021 RFA did not present a new question of medical necessity, so WCAB jurisdiction applies.
Official decision · page 6 → - ADJ16034617 · 2025-08-12 · Van Nuys District Office§ 4604
Determinative passage · p.8Finally, we note that the Labor Code expressly vests the Appeals Board with the authority for "the enforcement against the employer or an insurer of any liability for compensation imposed
The WCAB has authority to enforce valid UR determinations and resolve medical treatment controversies not subject to IMR.
Official decision · page 8 → - ADJ11423609 · 2022-09-12 · Los Angeles District Office§ 4604
Determinative passage · p.4However, section 4604 continues to vest with the Workers' Compensation Appeals Board (WCAB) the authority to resolve non-medical disputes arising out of the utilization review process. Section 4604 provides that: "[c]ontroversies between employer and employee arising under this chapter shall be determined by the appeals board, upon the request of either party, except as otherwise provided by Section 4610.5." (Italics added.) (Dubon v. World Restoration (2014) (79 Cal. Comp. Cases 1298 [2014 Cal. Wrk. Comp. LEXIS 131] (Appeals Bd. en banc).)
Defendant voluntarily submitted the matter as a medical dispute under section 4610 for further utilization review, waiving objection under section 4610(k).
Official decision · page 4 → - ADJ4274323 · 2014-10-06§ 4604
Determinative passage · p.1617 E. IF A UR DECISION IS UNTIMELY, THE DETERMINATION OF MEDICAL NECESSITY MAY BE MADE BY THE WCAB BASED ON SUBSTANTIAL MEDICAL EVIDENCE
The Board held that untimely UR decisions are invalid and medical necessity must be determined by the WCAB on substantial evidence.
Official decision · page 16 →
All 4 decisions naming § 4604 →
The rules written under this section
A statute says what is owed; Title 8 says by when, on what form, and what happens if the deadline passes. These name § 4604as what they implement.
- 8 CCR § 10290Petition Appealing Order Granting or Denying Petition for Order Requiring Employee to Select Employer-Designated Physician. [Renumbered]repealed
- 8 CCR § 10293Petition Appealing Order of the Rehabilitation Unit. [Renumbered]repealed
- 8 CCR § 10560Petitions Related to Orders Issued by the Division of Workers' Compensation Administrative Director or the Director of Industrial Relations.
- 8 CCR § 10950Petitions Appealing Orders Issued by the Administrative Director. [Repealed]repealed
Also on this
Unofficial guide — not legal advice. The statute is the state’s text. The quotes are litigated applications, not a prediction.
About California Labor Code § 4604
What is California Labor Code § 4604?
Labor Code § 4604 sits in ARTICLE 2. Medical and Hospital Treatment [4600 - 4615]. The statute on this page begins: Controversies between employer and employee arising under this chapter shall be determined by the appeals board, upon the request of either. The official display is on LegInfo; this is a reprint.
Did WCAB panels apply Labor Code § 4604 in this corpus?
This corpus has 4 released decisions whose extracted legal standards named § 4604. Quotes and PDFs are on this page. That is not every case in California that ever cited the section.