Rockley Photonics Patent Portfolio Analysis

One pulse, and everything before it

A $50M round, announced on the first of October 2020. On a timeline it is a single mark, and single marks invite a simple reading: this is where the work began. It is not. By the time that money was announced, Rockley Photonics had been filing patent applications for six years and nine months. The first family has a filing date of 20 January 2014.

That gap is the whole reason to read the rest of the file. Funding events tell you when other people became convinced. Priority dates tell you when the company itself was already committed, spending money on drafting and prosecution in a space nobody was yet writing cheques for. One of those two dates is a decision. The other is a reaction to it.

Two hundred and sixty ticks, mostly solid

Every family Rockley Photonics has on record sits on this arc. There are 260 of them. The solid amber ticks, 194 in total, are granted. The thin ones, 66, are published and still pending. That is a 75 percent grant rate across an eleven-year filing history, which is unusually high for a portfolio this size and this young.

Grant rates that high tend to mean one of two things. Either the claims were drafted narrowly enough to sail through, or the subject matter was genuinely uncrowded when the applications landed. The recent titles point at the second reading: an optical sensor module, systems for operating a spectrophotometer, a method for measuring pulse wave velocity, a wearable device with light source and optical sensor.

Seventy-five percent granted is not luck. It is either careful drafting or empty space.

The bars do not peak where you expect

Four families in 2014. Ten in 2015, sixteen in 2016, twenty-six in 2017, thirty in 2018, thirty-six in 2019. A steady climb, year on year, with no discontinuity anywhere in it. Then forty-two in 2020, the year the round was announced. The money did not start the curve. It arrived partway up a slope that had already been rising for six consecutive years without it.

The peak comes later: fifty families first filed in 2022, the highest of any year. Then the bars fall away, thirteen in 2023, four in 2024, two in 2025. Read the shaded band at the right edge before reading that fall as a stop. Applications publish roughly eighteen months after filing, so the most recent years are still partly invisible. The most recent published filing is dated 16 May 2025.

Who has been reading the file

Four organisations account for the heaviest citation traffic back into this portfolio. Taiwan Semiconductor Mfg Co Ltd cites these filings 72 times. Intel Corp cites them 56 times. Infinera Corp, 48. Celestial AI Inc, 46. Those are the nodes on the diagram, and the lines are simply examiner-recorded and applicant-recorded references pointing at Rockley families.

Note what the sector tag on this company says: Healthcare. Then note that the citing set is not a healthcare set. Citation is not endorsement and it is not permission, but it is evidence of attention. Four organisations have collectively pointed at this portfolio more than two hundred times, which means four sets of prosecution teams have had reason to read what Rockley filed.

Eight jurisdictions, filed deliberately

These families appear in eight patent offices, excluding PCT: the United States, the European Patent Office, China, Japan, Korea, Great Britain, Canada and Australia. That is not a default footprint. Each box represents translation cost, local counsel, separate prosecution and separate maintenance fees, chosen family by family over eleven years.

Here is the thread pulled tight. A company described as healthcare built a portfolio whose claims sit overwhelmingly in optics, began building it in January 2014, kept building it through six funding-free years, and reached peak filing volume two years after the $50M landed. The recent titles are wearables and spectrophotometry. The heaviest citers are semiconductor and photonics firms. The record says the optics came first and the application came second.

The sector tag describes the product. The claims describe the capability underneath it.

What the dates already told you

Every stage behind this one is a dated record. 2014 for the first family. 2020 for the money. 2022 for the peak. Eight offices, 194 grants, 327 named inventors across the whole body of work, with Yu Guomin and Aaron John Zilkie appearing most often. None of it is forecast. All of it is filed.

The question is what the shape of the curve means now. A portfolio that climbed for nine years and peaked in 2022 is either consolidating around what already granted or winding toward something the publication lag has not yet revealed. The shaded window at the right of the velocity chart is where that answer currently sits, and it will fill in on its own schedule.