Hmmm, that's a very good question. I've had FW fish lay infertile eggs in the past, so I suppose it's possible for SW fish to do the same. I've had FW Angelfish lay eggs, on a regular basis, even though there were only 2 female Angelfish in the tank. They'd each lay eggs, together, as if they were attempting to spawn with one another. FW Discuss are known to do the same thing.
Some FW live bearers are known to be able to "store" sperm, for many months, laying fertilized eggs, months after being fertilized. Though that obviously wouldn't be the case, with egg laying fish.