The very notion that the research arm of the United States Congress—which also happens to be the country’s oldest federal cultural institution and the largest library in the world—had interest in the public prattle of people publishing thoughts and links in real time, at 140 characters at a time, seemed farfetched. But the deal was done. With help from Twitter itself, the institution acquired all public tweet text (including by this author and this publication, as well as by countless members of Congress and several U.S. presidents) published between 2006 and 2010 and a promise to do the same in the years to come.

Unsurprisingly, Twitter has exploded in size (the company itself went public in Nov. 2013) and so the volume of so-called tweet text flooding into the library’s digital archives was growing exponentially. Eventually it would become too much. That day has come.

The Library of Congress announced on Tuesday that it would no longer ingest all public tweet text in 2018, instead choosing to “acquire tweets on a selective basis” beginning Jan. 1. It’s the same policy the institution applies to websites, which have naturally exploded in number since they first appeared decades ago.

“The Library [chose to collect tweets] for the same reason it collects other materials—to acquire and preserve a record of knowledge and creativity for Congress and the American people. The initiative was bold and celebrated among research communities,” wrote Library of Congress spokeswoman Gayle Osterberg on its website. “In the years since, the social media landscape has changed significantly, with new platforms, an explosion in use, terms of service and functionality shifting frequently and lessons learned about privacy and other concerns. The Library now has a secure collection of tweet text, documenting the first 12 years (2006-2017) of this dynamic communications channel—its emergence, its applications and its evolution.”

The Library says it plans to continue to preserve and secure its collection of tweet text. The collection as a whole will remain under embargo “until access issues can be resolved in a cost-effective and sustainable manner.”

“The Twitter Archive may prove to be one of this generation’s most significant legacies to future generations,” the institution wrote in a white paper announcing the policy change. “Future generations will learn much about this rich period in our history, the information flows, and social and political forces that help define the current generation.”