I count twelve different firms or practitioners who used “Fruitvale” in their sidewalk stamps. Here they are.
One dated example from 1915.
One example from 1927.
One example from 1926.
No dated examples.
No dated examples.
Examples from 1912 and 1914-1919.
No dated examples.
Examples from 1918, 1920, 1922, 1928, 1929, 1931, 1932 and 1936.
Examples from 1911 and 1922-24.
Examples from 1913-18, 1920, 1922, 1924 and 1927.
One example from 1912.
Examples from 1912 to 1915.
Conceivably there are others whose work survives only outside Oakland. I doubt it, though.
Oakland Underfoot 
26 February 2022 at 10:49 pm
Another one that’s not included above but that you’ve documented a number of times in your photos is W.N. Whitmore.
27 February 2022 at 11:59 am
Many thanks! Don’t know how I missed him, but now there are twelve.