This collage is from JD's site. The 2 patches bottom right are post 1905. The U.S. Trademark Act of 1905 required the "Reg US Pat Off." on labels
The patch below is pre 1905. Note the increased space between "Phila." and the baseball logo and the "A.J. Reach" at top fits easily within the seams of the baseball logo. All the patches above show the "A.J. Reach" overlap the seams by a fair amount. There are quite a few of the earlier examples on JD's site. http://www.baseballglovecollector.com The keystone logo was used quite early on their balls and bats. Gloves may have been the last to be identified, possibly some time in the 1890's.
The early example below is an anomaly to me. Reach did not make uniforms so it is hard to reference the evolution of their cloth patches. Reach did stamp some of their earlier equipment simply with "A.J. Reach Co." This patch may have been a reflection of that. The takeover by Spalding may also have influenced the Reach logo design in some way since both were competing for official league baseball status.