YC's best-funded startups are 3x as likely to de-anonymize you

By Installmap Research. Published 2026-09-27. Updated 2026-09-27. Version v1.0.

When we found 307 YC startup homepages running a script that tries to put a name on the visitor, we assumed they belonged to struggling companies trying to turn every visit into a lead. So we joined all 5,386 YC homepages from that crawl to Crunchbase funding data and to YC's own company directory. It went the other way. Companies with more money raised were more likely to run one of these scripts, and companies that YC lists as inactive almost never did.

The scripts come from 30 vendors. Most of them look up the company you are browsing from. Seven try to match you to a name and an email address.

YC visitor identification by funding statistics 2026

1. 53 of the 195 Y Combinator companies that have raised $100 million or more (27.2%) load a visitor-identification script on their homepage, against 114 of the 1,309 that raised under $1 million (8.7%).

Source: Installmap, YC's best-funded startups are 3x as likely to de-anonymize you, September 2026. Data: rendered homepage crawl of 5,386 YC companies, September 2026, joined to Crunchbase.

1. By last round, 9.1% of YC companies at pre-seed run one, 13.9% at seed, 23.8% at Series A, 27.1% at Series B and 35.5% at Series C.
2. 23.2% of the YC companies that YC's directory marks as hiring run one, against 9.4% of the rest.
3. 19 of the 195 companies with $100 million or more (9.7%) run a script that tries to name the visitor, against 50 of the 1,309 under $1 million (3.8%).
4. 2.3% of the YC companies listed as inactive whose site still loads run one, against 14.9% of active companies.

27.2% of YC companies with $100M or more raised run one, and 8.7% of those under $1M do

The share climbs from 8.7% under $1 million to 25.9% at $20 million to $50 million and levels off above that, at 28.4% for $50 million to $100 million and 27.2% for $100 million or more. Among YC's B2B companies the gap is wider: 42.2% of those with $100 million or more run one, against 12.2% of those under $1 million.

Qualified is the most common vendor among the 195 best-funded companies, on 18 of their homepages (9.2%).

50 YC companies with $100M or more raised run one on their homepage

Scale AI, Optimizely, Flock Safety, Solugen and Gusto have raised the most. Flock Safety, whose homepage sells license plate recognition cameras, runs Warmly, which tries to put a name and email address on each visitor. Teleport, which YC's directory calls "The Infrastructure Identity Company", runs Vector, another vendor that goes down to the person. Veriff, which sells identity verification for fraud prevention, runs ZoomInfo WebSights. Vanta, which sells automated compliance, runs three vendors.

17 of the 50 run a vendor that tries to name the visitor: Flock Safety, Solugen, Jeeves, Podium, Go1, Exa, Teleport, Plate IQ, Tennr, Numeral, Athelas, Instawork, Hubble Network, Encord, Axoni, Mezmo and Tranch.

We rendered all 53 homepages in this group again on 2026-09-27 and list only the vendors that loaded both times. Zip, Salt Security and Observe.AI dropped out.

Series C companies run one on 35.5% of homepages and pre-seed companies on 9.1%

117 of 1,287 pre-seed companies run a vendor (9.1%), as do 227 of 1,630 seed companies (13.9%), 108 of 453 at Series A (23.8%), 49 of 181 at Series B (27.1%) and 27 of 76 at Series C (35.5%). The 47 companies at Series D or later are at 19.1%.

23.2% of hiring YC companies run one, against 9.4% of the rest

YC's directory marks 1,460 of the companies as hiring, and 338 of them run a vendor (23.2%). Of the 3,926 that are not hiring, 369 do (9.4%).

2.3% of inactive YC companies run one

We then looked for the desperate companies we had expected. YC's directory lists 650 of the scored companies as inactive while their site still loads. 15 of them run a vendor (2.3%), against 614 of the 4,127 active companies (14.9%).

Companies whose last raise was three or more years ago are less likely to run one than companies that raised in the last 18 months, even at the same team size and traffic (odds ratio 0.57). A drop in traffic makes no clear difference: 22.4% of sites whose Semrush visits fell by more than 25% in a month run one, against 20.7% of sites whose visits held within 5%.

The obvious reply is that funded companies are bigger and have sales teams. Size is part of it, but money still shows at the same size. Among active YC B2B companies from the 2019 to 2022 batches with 11 to 50 staff, 44.7% of those at Series A or later run one, against 27.5% of those whose last round was seed or pre-seed.

Method

We fetched the homepage of every company in the YC directory with a headless browser on 2026-09-04. Of 6,133 companies, 5,386 had a homepage we could score (5,242 rendered, 144 from a plain fetch) and 747 had none.

A homepage counts when it loads a script from one of 30 visitor-identification vendors. Seven of them try to match the visitor to a name and email address: RB2B, Warmly, Vector, Retention.com, Customers.ai, Opensend and Hyros. The other 23 resolve the visitor's IP address to a company. HubSpot's built-in lookup and the LinkedIn Insight Tag are not counted.

We matched 4,508 homepages to Crunchbase by domain. 3,177 have a funding total, which counts every round Crunchbase lists, debt rounds included. Hiring, status and team size come from YC's company directory. METHOD.md in the dataset has the rest.

Limitations

• We see the homepage only, so every share is a floor.
• The shares come from one crawl. When we rendered 58 of the named homepages again three weeks later, 49 loaded the same vendors.
• Crunchbase funding totals are third-party figures, and 2,209 homepages have none.
• A script on the page does not mean it identified any given visitor.

Who paid

This report is self-funded. Nobody paid to be included or left out. Installmap sells technographic data exports.

Cite this report

Installmap Research, "YC's best-funded startups are 3x as likely to de-anonymize you", installmap.com, 2026-09-27, https://installmap.com/research/yc-best-funded-visitor-identification

Downloads

Files:

• domains.csv
• by_funding.csv
• by_round.csv
• by_hiring.csv
• best_funded_taggers.csv
• README.md
• METHOD.md

Data licensed CC BY 4.0. Source: Installmap, September 2026.