Writing prepared spells into a spellbook

[Crake]

I seem to recall somewhere it was written that if you had a spell prepared you could scribe it into your spellbook, expending the spell. Is this the case? And can you do the same thing with SLAs? Or do you need to have scribe scroll, scribe it, then copy it across?

[ksbsnowowl]

PHB p. 179

Replacing and Copying Spellbooks
A wizard can use the procedure for learning a spell to reconstruct a lost spellbook. If she already has a particular spell prepared, she can write it directly into a new book at a cost of 100 gp per page (as noted in Writing a New Spell into a Spellbook, above). The process wipes the prepared spell from her mind, just as casting it would. If she does not have the spell prepared, she can prepare it from a borrowed spellbook and then write it into a new book.

Duplicating an existing spellbook uses the same procedure as replacing it, but the task is much easier. The time requirement and cost per page are halved.

[Crake]

PHB p. 179

Ah ok, I was looking at writing new spells, not replacing/copying. What about using an SLA to scribe, say, if you had a racial SLA, or were a factotum with arcane dilettante?

[Kelb_Panthera]

Ah ok, I was looking at writing new spells, not replacing/copying. What about using an SLA to scribe, say, if you had a racial SLA, or were a factotum with arcane dilettante?

The rules are silent here but I'd be inclined to think that, since they're not spells, much less wizard spells, that you couldn't automatically succeed at putting them in a spellbook like a wizard with his prepared spells.

That said, there's no requirement that you even be a caster to scribe new spells into a spellbook as long as you can make the spellcraft checks.