William Entriken

William Entriken

Mission: Verify seller claims & authenticity for most things you buy

Philadelphia USA / 中国上海

Updated 2022-06-30

Lead author of ERC-721 standard

NFT drops

Email me if you need help buying/bidding on any of these.

First artist collaborations (one-of-ones)

Available on Rarible / 0.01 Ether
The Birth of an Idea
With Sean from ConwellsClub
Available on Mintbase / 1,000 NEAR
All Kindsa Media
With Living With Will, Julio Slim, Indigo
Available on Foundation / 1 ETH
Golden Landscape
With Hai von Son
Available on Mintable / 0.1 ETH
Ella's Dreams
With VjDeliria
Available on OpenSea / 1 ETH
On the road to El Chalten
With Elia Locardi
Available on Zora / 0.1 ETHSOLD

The first ERC-721 NFT

Su Squares about 6,500 left to mint

What's hot

Pacific Medical Training

We employ thousands of workers in entry-level medical jobs. We are also the world's first company to release CPR and advanced life support training courses when new science guidelines are published.

V.P., General Manager since 2013

Nineteen Eighty-Five

Nineteen Eighty-Five

A modern printing of the classic George Orwell book. Orwell’s protagonist battles with his own incriminating #searchhistory, the prying eye of the Social Justice Warriors watching him through his smart device

Published 2021

Blockchain standards

I promote intellectual property and stop fraud using blockchain. This standardizes the sale of physical assets on the Ethereum blockchain.

Engagement as an advisor to blockchain projects, training & developer relations for corporate accounts and code review for developers.

This work was sponsored in part by Ethereum Foundation.

I am hustling to answer everybody's questions about NFT. Day in and day out.

ERC-721 lead author since 2018

Civic projects


Eastern Montgomery County Chamber of Commerce, PA, co-chair government affairs committee board. We work with local, state and federal government representatives to connect local businesses with elected officials.

SEPTA rail scheduling

I consult with SEPTA to help set their rail schedules. Also, I independently measure On-Time Performance of all SEPTA trains. If you are ever late for work because of a late train, use my website as proof so you have an excuse.

Philadelphia Traffic Court

Philadelphia Traffic Court made national headlines throughout 2014 as its offices were raided by the FBI and 9 current and former judges face indictments on 77 counts. I successfully petitioned the Philadelphia government to make public their entire database of traffic violations. Now lawyers use it to appeal old tickets and some people have used the data to find evidence of wrongdoing.

Advisory and vulnerability research


My clients include: Arianee, EY, Light.art, Origins NFT, Lucid Sight (MLB Champions), Airbus A³, a checkout processor in the sports/events industry, TreasureDAO, Aleph Crypto Fund, defendant in an investor lawsuit, a hedge fund.

Code reviews

Some typical design and code review work I have done includes:

Privacy Log

I am active in doing technical research of smart contracts and websites. This includes work with the FBI and Apple. Usually I publish these on Privacy Log, and sometimes these publications are live zero-days if the vendor failed to take corrective action. (Of coures, I never post zero-days against paid advisory clients.)

Recent zero-days:

Monthly updates since 2008

Press coverage

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Self portraits for media

Speaking events (updates on Twitter)

I attend events to speak and give workshops based on invitations, client engagements, and the travel mantra.

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This work was sponsored in part by Ethereum Foundation.

More products and research

Personal blog

With analysis of football betting market inefficiencies, sentiment during the great depression, facial hair correlation to economic activity, and much musing. RSS


My sizes

  • 39L/40L suit
  • 33 slack / 33 inseam
  • 15 1/2 - 34/35 shirt

Best marathon time: 9h : 55m