Terms were not disclosed.
All of the Rams’ draftees have participated in a rookie minicamp and organized team activities, which concluded this week. A mandatory three-day minicamp begins Tuesday.
Everett was the 44th overall pick. Oakland Raiders defensive lineman Jihad Ward, the 44th pick in 2016, signed a four-year, $5.5-million contract, according to spotrac.com.
Kupp, a third-round pick (69th overall) from Eastern Washington, has been the most consistent rookie performer during workouts.
Jacksonville Jaguars defensive lineman Yannick Ngakoue, the 69th pick in 2016, signed a four-year, $3.5-million contract.
Johnson, a third-round pick (91st overall) from Boston College, has worked at both safety spots.
New England Patriots quarterback Jacoby Brissett, the 91st pick in 2016, signed a four-year, $3.4-million deal.
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