The original patent was filed by Tweetie designer Loren Brichter.
"I had started working on the patent two months before the Twitter deal," said Brichter. He filed the patent application one day before agreeing to sell Tweetie to Twitter. "The patent was the cherry on top," he says.
Notably, Brichter had concerns about how patents are being abused. "I have plenty of feelings about the patent system and how broken it is," he says. So to alleviate his concerns, Twitter has promised to only use the patent defensively. Meaning, the company won't sue other companies for using pull-to-refresh unless they sue Twitter first. Brichter says this is why he filed for the patent in the first place. "I realized that I'd invented something valuable and I could have a bullet in the chamber, god forbid."
Last April, Twitter announced the Innovator's Patent Agreement that promises not to use patents developed by employees for offensive purposes without their permission.
The IPA is a new way to do patent assignment that keeps control in the hands of engineers and designers. It is a commitment from Twitter to our employees that patents can only be used for defensive purposes. We will not use the patents from employees' inventions in offensive litigation without their permission. What's more, this control flows with the patents, so if we sold them to others, they could only use them as the inventor intended.
The full patent filing entitled, 'User interface mechanics' can be found here.