Greenspan, founder of PlainSite, found his online presence abruptly disrupted on June 13. The suspension of his account, which had more than 24,000 followers, raises questions about freedom of speech and online censorship. Ironically, Twitter claims defending and respecting the user's voice is one of its core values.

Greenspan gained a reputation for meticulously monitoring Twitter for any criticism directed toward Tesla and Musk. His vigilance in tracking and documenting litigation involving various companies, including Tesla, Twitter, General Motors Corp. and Meta Platforms Inc., made him a prominent figure in the world of online scrutiny. Over the years, Greenspan and Musk have found themselves entangled in legal disputes, further fueling the intensity of their interactions.

PlainSite served as a valuable resource for Twitter users, providing free access to state and federal court filings, public records and insightful analytics features for paying subscribers.

Greenspan's personal Twitter account was also suspended.

Even before gaining control of Twitter, Musk would take a proactive approach to addressing criticism.

Back in 2018, The Wall Street Journal reported that Musk actively monitored Twitter for tweets containing the hashtag $TSLA, often used by Tesla short-sellers. Musk would reach out to executives at companies to investigate employees who were potentially publishing negative tweets about his electric vehicle company.

During that time, Musk reportedly emailed former Volkswagen CEO Herbert Diess in July 2018, questioning whether one of Diess's employees was using Twitter to criticize Tesla anonymously. Business Insider later reported that Volkswagen determined the tweets were posted by the employee's brother.

Musk also allegedly texted Lawrence Fossi's employer. According to the WSJ, on July 23, 2018, Musk sent a text to the top executive at Fossi's company, asking the boss whether he knew his employee, known on Twitter as Montana Skeptic, "was obsessively trashing Tesla via a pseudonym," as disclosed in the report.

Following the incident, Fossi voluntarily deactivated his Twitter account and ceased writing for Seeking Alpha. Expressing his surprise at the extent to which Musk would go to quash criticism, Fossi commented, "I'm a nobody and he calls my employer?"

Following Musk's contact, Fossi ceased writing under the Montana Skeptic alias. He posted a farewell message on Seeking Alpha explaining that Musk threatened to sue him if he continued to write. He also stated, "Neither Mr. Musk nor Tesla has ever attempted, at any time, to contact me. Instead, Mr. Musk determined to go directly to my employer."

It was revealed that Fossi's employer was an early customer of Tesla's Model S sedan, according to a Tesla spokesperson cited by Business Insider.