NHL teams have until June 1st to sign their draft picks from 2012. If they are not signed, they will either a) re-enter the draft or b) become free agents (depending on their date of birth).
Here are the OHL players who remain unsigned.
Jarrod Maidens - Owen Sound Attack/Ottawa Sentaors
A 3rd rounder by Ottawa in 2012, Maidens has yet to return to the ice after suffering a nasty concussion in his draft year. He's made a few attempts but has encountered setbacks each time. Having not played a game in over two years, the Sens will most definitely let his rights expire. Maidens will re-enter the draft but will not be selected or looked at by an NHL team until he gets back on the ice. At this point, it would (sadly) appear that his promising hockey career is over.
Brady Vail - Windsor Spitfires/Montreal Canadiens
Despite putting up a pretty good year statistically, and earning a few looks at the AHL level the past two years, it appears that the Canadiens still seem unsure as to whether they'll sign Vail (their 4th rounder in 2012). While Vail did have a solid year, he hasn't exactly grown to become the dominant two-way center that Montreal envisioned he'd become. Are they thinking that he might be a bit of a tweener? Doesn't possess the pure skill necessary to be a top 6 player, but hasn't grown a lot as a player away from the puck and doesn't profile as a dominant checking player either?
Gemel Smith - London Knights/Dallas Stars
A big acquisition by London this year, Smith was a pretty big disappointment for the Knights and ended up being relegated to the 4th line by the end of the Memorial Cup. While he's quick and elusive, Smith doesn't have elite size or skill. His energy level and two-way game also regressed, and his ability to play through traffic never really matured. At this point, I'd consider him a long shot to be signed by Dallas.
SIGNED BY DALLAS
Michael Clarke - Peterborough Petes/Colorado Avalanche
Drafted with the expectation that he'd develop into a rugged, two way center with scoring ability. But that never came to fruition. Clarke continued to struggle with consistency and his game didn't progress enough in the areas it needed to (skating, board play, defensive awareness). Highly doubt he's signed. However, he will make a great overager for a Peterborough team that could make some noise in the East next year.
Clark Seymour - Peterborough Petes/Pittsburgh Penguins
It's already been stated that he won't be offered a contract by Pittsburgh, which will make the Petes' alternate captain and overager a free agent. Seymour turned himself into a pretty useful stay at home defenseman at the OHL level, but just isn't at the level where you'd consider him a serious NHL prospect. Seems like a pretty good bet for a CIS spot next year.
NOT SIGNED (now a free agent)
Cody Payne - Saginaw Spirit/Dallas Stars
Drafted by Boston, but traded to Dallas, Payne had a good year statistically for Saginaw. He finished second on the team in goals with 26. However, his physical game and energy level regressed this year and Dallas has already stated that he won't be offered a contract. Payne will re-enter the draft and I doubt he'll be re-selected. He'll return to the OHL as an overager and will look to find a balance between scoring and playing a power forward game.
Jesse Graham - Saginaw Spirit/New York Islanders
Graham had a pretty good year in 2014, setting career highs in nearly every statistical category. He also (apparently) played quite well for Bridgeport in a brief stint at the end of the year. While undersized, his exceptional skating ability and strong play with the puck still make him an intriguing prospect. He's the only player on this list that I suspect may still get an NHL contract. However, the Isles do have a lot of depth at the position currently so they may not see a fit in their organization for him. Could be a good candidate to earn an AHL deal next year instead of returning to the OHL for an overage year.
SIGNED BY NYI
Joseph Blandisi - Barrie Colts/Colorado Avalanche
Blandisi is a hard worker and a valuable OHL player. He has enough skill and determination to make it as a character/energy player at the next level. But I'd still be surprised if Colorado signed him at this point. Blandisi would then re-enter the draft and should he not be taken, will return to Barrie for his overage year.
Gianluca Curcuruto - Plymouth Whalers/Columbus Blue Jackets
After a really strong (bounce back) year in 2013, Curcuruto regressed in 2014 and did not have a strong season. The Whalers' struggled at times defensively (luckily they had Nedeljkovic) and Curcuruto was right in the thick of that. He's a player who currently lacks an identity. He's never really developed into an elite defensive player, but can lack the confidence in his offensive game that would make him an elite puck mover. Columbus has already stated that he will not be signed, so he'll re-enter the draft.
*Of note, Oilers 3rd rounder Daniil Zharkov, and Devils 6th rounder Artur Gavrus (both former OHL'ers) do not have to be signed because they are considered "defected players."