One assignee leads the ranked field with 65 records, far ahead of the fifth-ranked company’s 4 records and the tenth-ranked company’s 2. The ranking covers 33 companies total drawn from 104 records in scope, so the field has one dominant filer and a long tail of narrower, specific filers. Anyone assessing freedom-to-operate on core attenuation-correction or co-registration methods should check this leader’s portfolio first, since its filing volume covers most of the foundational correction techniques in this dataset.

In PET imaging, photon attenuation as radiation passes through tissue must be corrected for accurate reconstruction, and that correction relies on an attenuation map normally derived from a CT or MR scan. In hybrid systems, the morphological scan is often truncated relative to the PET field of view, leaving gaps in the map — a problem that a large share of the filings in this dataset (grouped under image data processing and radiation measurement IPC classes) exist specifically to solve. It matters for patent strategy because it is the single busiest claim area in the field, meaning new filings here face the densest prior art.

The filing trend in this dataset peaked at 7 records in 2019 and has not exceeded that level in any subsequent year through the 2026 data cut-off. That does not necessarily mean interest is declining — publication typically lags actual filing by roughly 18 months, so the most recent one to two years in any trend chart will understate true filing activity. Read the trend as a steady, mature filing pattern rather than either growth or decline until more recent years fully publish.