The most common sankaku techniques you see in competition are yoko-sankaku and reverse sankaku. Ushiro-sankaku is somewhat rare although Lucy Renshall of Great Britain specializes in it. Interestingly, she often does a hold-down or an armlock from it and not so much a strangle. The way she comes up on top for the hold-down however might no longer be considered legal under the new rules.
The following examples are considered legal:
The following are NOT allowed:
Blog posts
A look back at Takato's remarkable career.
Japan’s Good Problem in the -90kg Division
Japan has two World Champions in the -90kg division. Who will go to the Olympics?
Murao is the World No. 1 but there's one player he hasn't been able to beat.