Provides that the experience rating factor must provide equal weight to the ratio between payments made by the second-injury fund for claims of the self-insurer to the total payments made by the second-injury fund by all self-insurers for the prior three fiscal years and the ratio of workers' compensation claim payments under this title made by the self-insurer to the total worker's compensation payments made by all self-insurers under title 51 RCW for the prior three fiscal years. This average must be divided by the latter ratio to arrive at the experience factor.

Provides that, if the outcome study conducted by the department of labor and industries under this act shows a negative impact of fifteen percent or more to workers following claim closure among nonpension self-insured claimants, 2005 c ... s 1 (section 1 of this act) expires June 30, 2013.

Directs the department to conduct an outcome study of the experience rating system established in 2005 c ... s 1 (section 1 of this act). In conducting the study, the department must: (1) Compare the outcomes for workers of self-insured employers whose industrial insurance claims with temporary total disability benefits for more than thirty days are closed between July 1, 2002, and June 30, 2004, with similar claims of workers of self-insured employers closed between July 1, 2009, and June 30, 2011;

(2) Study whether the workers potentially impacted by the experience rating program have improved return-to-work outcomes, whether the number of impacted workers found to be employable increases, whether there is a change in long-term disability outcomes among the impacted workers, and whether the number of permanent total disability pensions among impacted workers is affected and, if so, the nature of the impact; and

(3) Develop, in consultation with representatives of the impacted workers and the self-insured community, a study methodology that must be provided to the workers' compensation advisory committee for review and comment. The study methodology must include appropriate controls to account for economic fluctuation, wage inflation, and other independent variables.

Requires the department to report to the appropriate committees of the legislature by December 1, 2012, on the results of the study.