Amid all the 50th-anniversary remembrances of Woodstock, the names of a few performers are likely to show up as shorthand for that historic weekend in 1969. Janis Joplin and Jimi Hendrix, for example, both of whom were well-known acts when they attended the three-day event. Or maybe someone like Carlos Santana, whose band became a sensation thanks in large part to their appearance at Woodstock and their spectacular 11-minute instrumental, “Soul Sacrifice.”

One name that’s less likely to show up: Bert Sommer. Sommer is one of the many Woodstock performers whose mainstream fame has not endured that half-century, and that’s a story worth telling too.

“My dad was a big presence, a self-taught musician who found his way as poet and songwriter. He had a lot of opportunities,” his son Jesse Sommer says, 50 years after his father’s big moment. “We all wish it had gone down a different route. With the type of voice he had, he should have been more well-known then he was. I don’t want to say it was the ‘Woodstock Curse,’ but there were things that were always preventing the next step.”

Bert Sommer was the perfect poster boy of the era. The 20-year-old singer-songwriter from Long Island, N.Y., was hard to miss. A Tim Buckley lookalike, he sported shoulder-length curly hair, a headband, bare feet and a voice like a dove’s.

As a teenager, Sommer had begun writing songs for local bands such as Leslie West’s The Vagrants, through whom he met guitarist Ira Stone. More success followed as a member of the Left Banke with Michael McKean. Record producer Artie Kornfeld first met Sommer in 1969 when he came to see him at Capitol Records. “He played some stuff on his guitar and I fell in love with him,” Kornfeld says from his home in Delray Beach, Fla. “He was a great guy.”

Kornfeld became an advocate for Sommer’s music. He recorded Sommer’s first solo album, The Road to Travel, on Capitol Records. A few months later Sommer landed a role in the musical Hair in Los Angeles. Three months later he was in the show on Broadway with Ben Vereen and Jennifer Warnes.

Meanwhile, Kornfeld teamed up new business partners, Michael Lang, John Roberts and Joel Rosenman. Their goal was to put on the largest event in music history. That event was Woodstock, and Kornfield brought Sommer along to perform in his first big concert.

Festival staff were still finishing the stages when the festival opened on Aug. 15 with a performance by Richie Havens. Sommer was on the program for later that night.

“Me and my wife Maxine went up the night before and stayed in a hotel,” recalls Stone, one of two of Sommer’s musicians who got stuck in the infamous traffic jam on the way to Woodstock. “We had no idea,” he says. “I thought it was going to be a music and art stand with people selling their wares.” A helicopter was sent to get them over the hill in time for the set.

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The baby-faced Sommer, whose name was mispronounced on stage, began his 10-song set with “Jennifer,” a song he’d written about Jennifer Warnes, who was also in the cast of Hair. Sommer had his first taste of professional exposure as a singer-songwriter in front of nearly a half a million people. His version of Simon & Garfunkel’s ballad “America” received a standing ovation, and in Kornfield’s memoir The Pied Piper of Woodstock he recalls the moment as “simply electrifying,” writing that “Paul Simon later said that Bert’s rendition [of ‘America’] on record that I produced, was better than Simon & Garfunkel’s. I’ve been told that this performance was the only standing ovation at Woodstock.” (As Kornfield also noted, Sommer turned this into a joke: “Yeah, I got the standing ovation… on their way to the bathrooms!”)

For a brief moment Sommer was on top of the world.

But when Warner Brothers acquired the rights to the festival, Kornfeld’s say in the festival’s afterlife essentially ended there, as the Wall Street Journal’s Jim Fusilli explained when he investigated Sommer’s story in 2009, and so did his ability to protect the artist he had supported. The 1970 Michael Wadleigh Woodstock documentary didn’t include Sommer, and nor did the soundtrack that followed. Kornfield told Fusilli that the omission was because Sommer had signed with Capitol, a Warner’s competitor. (The Grateful Dead, Janis Joplin and The Band were also excluded in the original film and album.) When a commemorative plaque was installed at the site of Woodstock, he was left off. His name has never appeared in print in TIME.

A plaque marks the original site of the Woodstock music festival, seen Aug. 14, 2009 in Bethel, N.Y. Mario Tama—Getty Images

So, despite being involved in two of the most famous counterculture events of the ’60s — Hair and Woodstock — and despite having that standing ovation and a 10-song set, Sommer’s name was somehow always left out on the historical recollection of all things Woodstock over the years. It felt to him, friends say, as if he didn’t exist.

“He was really upset about that,” his son, Jesse, tells TIME.

And, while Woodstock success was certainly not a guarantee of fame, the lack of recognition didn’t help.

“It killed Bert that he was not on the commemorative plaque slab,” recalls his friend Rick Bedrosian. “People would notice he was at Woodstock. He’d say, ‘Yeah, yeah and two dollars gets me a cup of coffee!’” Bedrosian notes that the Bethel Woods Museum does have a short documentary on the Woodstock Festival and includes Sommer’s name in various exhibitions. “Its not a huge presence but it’s there,” he says.

Ira Stone continued playing gigs with Sommer, who recorded a total of five albums and had a hit with “We’re All Playing in the Same Band,” a song he wrote about Woodstock. In 1976 he appeared on the television series Kaptain Kool and the Kongs. In 1977 Paul Shaffer arranged the music on his second album, Bert Sommer. “One of my most vivid memories is opening for Poco at Carnegie Hall,” says Stone.

“He spoke to me about Woodstock. He was very proud, very happy to be part of it, yet he definitely felt that due to different views or contractual agreements, he was cheated out of a rapid rise to fame,” says Jesse Sommer.

“It’s the man who spends his life 10 feet from gold,” he adds. “It’s right there, just a little askew.”

Bert Sommer died at age 41 on June 23, 1990 — but it’s now possible to hear his music.

In 2005, producing partners Andy Zax and Brian Kehew came across the Woodstock recordings in the Warner Brothers Vault. For the 50th Anniversary, they put together the 38-disc box set Woodstock 50 — Back to the Garden — The Definitive 50th Anniversary Archive (Rhino Records). It includes every note of music played at the festival (save for three songs) — including, on the 38-CD box, all of Sommer’s songs that were previously left off.

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