Enron manipulated their stock price and used special purpose entities to sell off their debts. They also used mark-to-market accounting practices to rate their financial health based on future earnings rather than their current worth, which ultimately led to their downfall.
Enron was named America's most innovative company for six years in a row, but their many investments and schemes did not always pan out financially, despite being ahead of their time in certain ventures such as broadband and video on demand in the early 2000s.
Enron used special purpose entities to dispose of toxic assets and borrow against them, all while keeping their stock price high, in a house of cards that eventually came crashing down.
Enron's CFO Andrew Fastow led a manipulative scheme using his sub-corporation LSM and mark-to-market accounting to inflate the company's market cap to $70 billion by August 2000, making it the seventh largest publicly traded company in the world at the time. Mark-to-market accounting is a narrow purpose entity intended to rate the financial health of companies based on future earnings rather than current worth.