Office towers, warehouses with temp labor, stores inside malls: shared sites mean overlapping employers, and SB 553 has specific rules for how their plans fit together. Every employer keeps its own plan, the coordination section does the real work, and the log rule assigns exactly who records what.
A lot of California workplaces have more than one employer on site. An office tower holds dozens of tenants. A warehouse runs its own crew next to staffing-agency temps and a separate janitorial contractor. A retail store sits inside a mall with its own security force. Workplace violence does not respect payroll boundaries, and Labor Code 6401.9 was written with that in mind. SB 553 has specific rules for how employers on a shared site are supposed to fit their plans together, and they are the part of the law most single-site summaries skip.
The first thing to get straight: a shared site does not mean a shared plan. Each employer at a multiemployer worksite establishes, implements, and maintains its own workplace violence prevention plan. The building's plan does not cover your employees, and yours does not cover the contractor's. What the statute requires on top of that is coordination: your plan must include the methods you will use to coordinate implementation with other employers, so that every employer and every employee understands their respective roles.
That coordination section is not decorative. The statute says the methods must ensure that all employees receive the required training and that workplace violence incidents involving any employee are reported, investigated, and recorded. If your coordination plan is a sentence that says "we will coordinate with other employers," it does not do either of those things.
The statute assigns the violent incident log at a multiemployer worksite precisely: the employer whose employees experienced the incident records it. That employer also has to provide a copy of the log to the controlling employer, the entity running the site as a whole. So after an incident, at least two employers hold records, and the personal identifying information rules still apply to both.
This is where shared sites quietly break. An incident involving a temp worker gets reported to the agency, the agency assumes the host employer logged it, the host assumes the agency did, and the controlling employer never sees a copy. The statute closed that loop in advance; the coordination methods in each plan are supposed to make the handoffs explicit before anything happens.
Three patterns show up repeatedly. First, temporary labor: the temp worker who does not know which employer to report a threat to, and whose training was handled by nobody because each employer thought the other did it. We covered the temp-labor seam in detail in our post on SB 553 for warehouse and logistics employers. Second, common areas: lobbies, loading docks, parking structures, and shared corridors belong to the site, and every tenant plan should say whose procedures apply there. Third, contractors on short engagements: a vendor working on site for two weeks is still an employer with employees to protect, and the host's coordination methods have to account for them.
In practice it is unglamorous. A short written exchange between employers that names who trains whom, who logs what, and who gets copies. A reporting path that works for every badge on the site, not just the host's employees. A joint walk of the shared areas so each plan's hazard section describes the same physical reality. And a check, at least at the annual review, that the other employers on site are still doing their part, because staffing and tenancy change faster than plans do.
The statute's expectation is simple: on a shared site, an employee of any employer should be able to report a threat, get trained, and have an incident recorded without the employers arguing afterward about whose job it was. If your site cannot produce that outcome today, the coordination section of your plan is where the work is.
If you run a multiemployer site, or you are one employer inside one, sorting out these seams is part of our SB 553 compliance work. Book a consultation and we will map the responsibilities with you.