Most legally scoring pins come under one of the 10 osaekomi-waza classifications. However, I have seen a couple of unconventional pins which do not obviously appear to fall under any of these:
Unconventional osaekomi-waza
What differentiates these from traditional pins is that tori is controlling uke from behind, holding from behind their head and using tension in the gi (or an inverted headlock) to pin them, as opposed to using their bodyweight on top of uke.
SRT / Funakubo-gatame
A technique favoured by Matsumoto Kaori and Funakubo Haruka, a variation of the "Super Rolling Thunder" (SRT) / stomach wrap turnover. Here tori usually prevents rotation in the other direction by also holding the belt/pants of the opposite side of uke:
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Examples |
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- WC Seniors 2015 - WC Juniors 2015: 1, 2, 3 |
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A similar technique from An Baul |
Matsumoto headlock / Wrestling's "Assassin"
When going for an anaconda choke, instead of rolling to finish the submission tori can push uke back or step over them to end in a pin:
Sankaku holds
Some variants of pinning sankaku positions are (to my knowledge) not covered under the standard pin classifications, but still qualify as osaekomi.
This is a pin which seems to be inspired by wrestling's "Bow and Arrow" but with control of both legs with a triangle instead of just one (necessarily because of judo rules regarding limb control by uke in osaekomi).
It is taught by Koji Komuro and has been used to success multiple times by Miku Tashiro involving trapping uke's legs with a leg-triangle, and then controlling their upper body from the outside by holding either an arm or their neck/collar.
Non-scoring pins
There are a number of unconventional pins which are unclassified but are non-scoring or illegal. These also are differentiated from usual pins in that control comes from behind uke's body:
Seated on side-ribs
This pin is no longer considered valid for scoring since uke's arm is not between the legs, and thus no control over it (IJF Referee & Coach Seminar 2016 - Part 1 (7:20:10)).:
"Crucifix"
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Description |
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There is also the crucifix hold, which as far as I'm aware does not come under any of the official Kodokan pin groupings. Note: the Kodokan used to designate the collar choke executed from this position as jigoku-jime, but I believe it is now officially considered a variant of okuri-eri-jime. |
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Mifune's ura-gatame ("Crucifix") This pin is considered non-scoring since tori's body is underneath uke's. |
Headlock (without arm)
Additionally there are headlock pins which are illegal due to potential danger to the neck:
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"This kind of osaekomi-waza is not valid and the referee must call mate immediately." "It is never allowed to hold an osaekomi just around the head/neck without control of at least one arm." - Ibid. |