The assignee ranking covers 100 companies drawn from the 72,117 records in scope, led by a mix of telecom equipment makers, semiconductor firms and university research offices. The top 5 combined hold only 6.2% of all records and the top 10 hold 10.6%, so ownership is spread across many filers rather than concentrated in one or two dominant portfolios. That pattern means competitive tracking needs to look past the largest names to the long tail of mid-size and single-filing entrants who still hold meaningful claim positions.

Filing volume rose through the late 2010s and peaked at 1,400 in 2021, then declined to 791 by 2024, a documented -44% drop over that three-year window. Years from 2025 onward are still incomplete in the data because patent publication typically lags filing by around 18 months, so those figures will keep rising as more filings publish. The honest read is a genuine pullback from a 2021 peak in the years where the data is complete, not an ongoing collapse.

Optical elements and systems, IPC class G02B, is the largest single category at 12.7% of the 72,117 records in scope, reflecting how much of the field’s claim activity sits in lenses, waveguides and optical assemblies rather than active components. Optical control and modulation (G02F, 4.8%), general transmission (H04B, 4.3%) and lasers and stimulated emission (H01S, 4.0%) follow behind. Because records often carry multiple IPC classes, these percentages overlap rather than summing to a whole, so no single class should be read as a majority of the field.