The indictment of Kody Knudsen of Springs was unsealed yesterday in the county courtroom of Justice Martin I. Efman in Riverside. Mr. Knudsen, 28, has spent much of his adult life behind bars, a trend that is all but certain to continue. The grand jury charged Mr. Knudsen, who was arrested early on the morning of May 11, with 13 Class B and A felonies, the most serious level, all related to alleged drug dealing.Beginning on March 17, East Hampton Town police said, Mr. Knudsen made a series of sales of small amounts of cocaine from his Hollyoak Avenue residence to an undercover agent working with the county district attorney’s East End Drug Task Force. After making several similar sales over a two-month period, police said he made a bigger sale — over half an ounce of methylenedioxy-methamphetamine, commonly known as Molly or Ecstasy — to the same agent.Mr. Knudsen, from the file on record at East Hampton Town Justice Court, made at least six sales of narcotics to the agent over the two-month period. Town police said neighbors concerned with the unusual amount of foot traffic in and out of the house alerted them to possible criminal activity.In court last Thursday, Matthew D’Amato, Mr. Knudsen’s attorney, told Justice Steven Tekulsky, who had remanded Mr. Knudsen to county jail without bail the week before, that negotiations leading to a guilty plea, a process called a superior court information, were continuing. The hope for the defendant, apparently, was to avoid an indictment, but as of yesterday’s unsealing that is off the table.Mr. Knudsen’s criminal history began in 2007, when he was 18 and allegedly stabbed an acquaintance. He was given youthful offender status in that case, and the court file is sealed.In 2008, he was charged with burglary and resisting arrest. The felony burglary charge was eventually dropped, but he pleaded guilty to a misdemeanor count of resisting arrest and was sentenced to 120 days in jail. In 2010, he was convicted of assault with intent to cause serious injury, a felony, and was sentenced to two years in state prison.Since serving out that sentence, he has been arrested numerous times on charges related to violence, and has been convicted twice for drunken driving, once as a misdemeanor, the second, in 2015, as a felony, which led to more time behind bars.Justice Efman set bail at $100,000, which was not met. Mr. Knudsen, who pleaded not guilty, remains in the county jail.