Cognomen 信也 (信也 
) , in the world, is an extremely rare last name. Much more frequently, 信也 is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| 信也 | China |
| 坂井 信也 JP (b. 1948) |
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| 宮谷 信也 Japanese tarento and owarai tarento, JP (b. 1969) |
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| 武井 信也 JP (b. 1971) |
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