Ray Dalio has practiced transcendental meditation since 1969.

True: credible accounts (Dalio's own consistent accounts in books and interviews, or profiles) show he learned Transcendental Meditation in 1969 (or 1968) and has practised it ever since. Mostly true: he started within about two years of 1969, or practised with some gaps but substantially continuously. Mixed: he started much later (early-to-mid 1970s), or practised only intermittently. Mostly false: he began meditation around then but not TM specifically, or took up regular practice only much later. False: evidence shows he began TM after 1980 or does not practise it.

Set before the research began.

1. E1 Ray Dalio and Mario Batali Meditate on the Secret of Their Success Institutional Investor · 28 February 2014

   “Dalio, for his part, has been meditating for 42 years.”

2. E2 Ray Dalio and Mario Batali Meditate on the Secret of Their Success Institutional Investor · 28 February 2014

   “are both big devotees of Transcendental Meditation, which was introduced to the West by India’s Maharishi Mahesh Yogi a half-century ago.”

3. E3 Ray Dalio's Beatles-inspired routine for success CNBC · 23 August 2019

   “Dalio was in his early twenties when he was inspired by the famous foursome to take up a new skill: Meditation.”

E2, a 2014 independent profile, describes Dalio as a big devotee of Transcendental Meditation, which supports the claim that he still practised it. The same article (E1) says he had been meditating for 42 years as of February 2014. That points to a start around 1971–1972, roughly two to three years after the 1969 he gave. E3 says he took up meditation in his early twenties, without giving a year. Together the sources support long, ongoing TM practice that began around the claimed time, but they don't confirm 1969 exactly.