Approach as per the excellent description given on the main Sharkstooth
page. In the summer, start early enough that you can be off the summit before the usual afternoon thundershowers roll in. Don’ t underestimate the time required to reach the base; expect about 2-3 hours. Bivying in the Gash is also an option. As you approach within about 200 vertical ft of the col at the top of the Gash, you will see a very prominent buttress or fin projecting out from the right side of the east face. This is the Northeast Ridge, and the base of the climb is approached from ledges on the climber's left of the ridge.
The three routes listed in the Gillett guidebook on the east side of Sharkstooth are:
East Gully: 5.4; East Face: 5.4; Northeast Ridge: 5.6
There aren’t necessary exact lines unique to each climb since the rock is so broken that basically anything between the East Gully and Northeast Ridge can probably be climbed at a moderate rating. The East Face route ends on the last pitch of the Northeast Ridge. What I describe may not be the actual line, since there was another group on the route when we did it, and we stayed left of them for almost the entire route.
For the Northeast Ridge, start from the ledges described above. The first two pitches can go almost anywhere along the approximately 100 ft wide ridge. We stayed to the left side, almost on the arête. At the end of the second pitch, we turned right up a loose chimney to reach a series of small ledges holding some loose rubble. Pitch 3 heads left around a left-facing flake and enters a very fun left-facing dihedral (5.6). The exposure has increased dramatically at this point. After the dihedral, we headed left again to stay near the arête and did one more pitch to a huge ledge that looks down onto the Petit Grepon and The Saber. Pitch 5 heads up the obvious wide crack (5.5) and stays along the ridge until another large ledge at a notch in the ridge is reached. We did an alternative start to pitch 5 that heads left around a corner and up a chimney with two cracks in the back, pulls over a small roof (maybe 5.8), and rejoins the ridge. Pitch 6 follows the very exposed but easy crest of the ridge (5.4) to the flat summit block. From here, it's an easy stroll to the top.
Also, watch out for loose rock. Sometimes what appear to be solid horns are detached flakes only held in place by friction and moss. The day we did this route, another party was hit by rocks they knocked down.
Descent is down the East Gully. Just south and about 20 ft below the summit is the first rappel station (3 pitons and a slung block). Back it up with slings if in doubt. Double ropes will take you all the way to the next anchor, although a single rope will take you to a large grassy bowl that can easily be downclimbed to the next anchor. The next long double rope (60 m) rappel leads off a slung boulder with a piton to a fixed gear anchor on the climbers right side of the gully. Several other rappel stations are passed along the way, which could be used for single rope rappels. A final single rope rappel takes you to easy terrain that can be downclimbed back to the Gash and the start of the climb.
Protection throughout this route is excellent and plentiful. My recommendations include:
1 set of stoppers
Maybe a few small hexes
Finger to hand-sized cams
Plenty of runners
Also, I didn't do the off-width crack on pitch 5 , but I think larger cams would protect it.
Either double ropes or single 60 m will get you down the rappel.
Definitely wear a helmet.
Even though we hung our packs on an overhanging boulder at the base of the climb, a marmot was still able to unzip the packs and eat our lunches. As if that wasn’t enough, he took a crap right on top of one of the packs (luckily not mine). Like other areas of the park (Glacier Gorge and Chasm Lake especially), the marmots are habituated to humans, and probably obtain a good portion of their sustenance from looted backpacks. Either carry all your food or hang it better than we did.