Marin - about 400 tests; 30 positive; 1 new hospitalization; no deaths. The county did not update the geographic info.
Separately: San Quentin total active cases now 456 (up 91)
A few weeks back, Marin had among the lowest case counts as a fraction of population (see note below) of the Bay Area counties. Now, mostly because of the hotspot in San Rafael, it has the highest.
Case counts here are: 7 day average new cases as a fraction of population. So, Marin's recent average of 27 cases per day vs its population of 251k = 109 / million people / day. And this excludes the outbreak at SQ prison.
Sources: SFist .csv files, from which I subtracted by hand the San Quentin active case data.