Cal. LAB § 4751

(a) If an employee who is permanently partially disabled receives a subsequent compensable injury resulting in additional permanent partial disability so that the degree of disability caused by the combination of both disabilities is greater than that which would have resulted from the subsequent injury alone, and the combined effect of the last injury and the preexisting disability or impairment is a permanent disability equal to 70 percent or more of total, the employee shall be paid in addition to the compensation due under this code for the permanent partial disability caused by the last injury compensation for the remainder of the combined permanent disability existing after the last injury as provided in this article, provided that one of the following circumstances exist:

(1) The preexisting disability or impairment was to a hand, an arm, a foot, a leg, or an eye, and the whole person impairment percentage resulting from the subsequent injury is to the opposite hand, arm, foot, leg, or eye, and the latter whole person impairment percentage, when considered alone, after apportionment, is equal to 5 percent or more of total.

(2) The whole person impairment percentage resulting from the subsequent injury, when considered alone, after apportionment, is equal to 35 percent or more of total.

(b) An employee who sustains an industrial injury that results in 100 percent permanent total disability is not entitled to additional compensation from SIBTF.

(c) An employee who receives an award of additional permanent disability payments from SIBTF based on 100 percent combined permanent disability shall not apply to SIBTF again for additional permanent disability payments.

(d) An employee shall provide the director with all documentation and any other information as may be required by the director, in their discretion, to determine the employee’s eligibility for SIBTF benefits.

(e) Liability by SIBTF for any additional permanent disability benefits under this article shall commence upon a final determination of SIBTF liability and after any reduction pursuant to Section 4753. Any payments by SIBTF under this article shall commence within 30 days of the final determination of SIBTF liability.