A long run of them were about proving a person is who they say they are.

Sending a code to a phone, calling a number back, checking a login against something the account holder physically has. Authentication and notification patents cover the plumbing behind that, and they are heavily litigated because almost every consumer service now depends on them.

  • Twilio v. TeleSign Patent Trial and Appeal Board. U.S. Patent 7,945,034. Obviousness assertions against a fraud detection process based on a user's telephone number were rejected by the Board.
  • TeleSign v. Twilio Central District of California. U.S. Patents 7,945,034; 8,462,920; 8,687,038; 9,300,792. Three inter partes reviews defended.
  • StrikeForce v. PhoneFactor and StrikeForce v. Microsoft District of Delaware. U.S. Patents 7,870,599; 8,484,698; 8,713,701. Out of band authentication.
  • SimpleAir v. Microsoft Eastern District of Texas. U.S. Patents 7,035,914; 6,021,433.

Several were about keeping information from being read by the wrong people.

Cryptography, encoding and computer security. These cases turn on mathematics that predates the products by decades, which means the prior art is deep and the prosecution histories are long.

  • Princeton Digital v. Microsoft District of Delaware. U.S. Patent 4,813,056.
  • Tallgrass v. Microsoft Eastern District of Texas. Addison Fischer Patents 5,346,972; 6,141,423; 6,216,229.
  • Pantaurus v. Microsoft Eastern District of Texas. U.S. Patent 6,272,533.

Several were about getting a message, or an image, from one place to another.

Communications, email and imaging. The patents in this group tend to be older than the accused products by a long way, so the argument frequently becomes what a phrase written in the nineties can be made to cover today.

  • Comcast v. Sprint Eastern District of Pennsylvania. U.S. Patent 5,991,271.
  • InNova v. Cinemark Eastern District of Texas. U.S. Patent 6,018,761.
  • E-contact v. Microsoft Eastern District of Texas. U.S. Patent 5,347,579.
  • Skyline v. Microsoft Eastern District of Virginia. U.S. Patent 7,551,172.

Two were about industrial chemistry rather than software.

Chemical patents behave differently in court. The claims describe compositions and processes rather than steps a computer performs, and the expert testimony reads like a laboratory notebook.

  • Buckman Laboratories v. Solenis Western District of Tennessee. U.S. Patents 8,841,469; 8,962,059. Argued at the U.S. Court of Appeals for the Federal Circuit.
  • Buckman Laboratories v. Nalco Northern District of Illinois. U.S. Patents 7,949,432; 8,012,758; 7,981,679.

Two were about a name rather than an invention.

Trademark disputes are often decided at the Trademark Trial and Appeal Board rather than in a courtroom, and they turn on whether ordinary buyers would be confused, not on what the technology does.

  • Cancellation proceeding defended On behalf of a fashion company.
  • Opposition pursued On behalf of a non-profit organization.

These are matters reported publicly by the firm. Every case turns on its own facts and its own record, and past results do not guarantee a similar outcome.

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