"The Etruscan forms in -si and -(a)le can be used to designate both by whom and for whom the object was made (Steinbauer 1999:174-6)."In case the absurdity isn't noticeable, "by whom" and "for whom" are opposite roles in these inscriptions. How did this nonsensical statement make its way to modernday print? What happened to the concept of structured, coherent grammar? In his solitary example of ET Fa 3.4, a vessel from Vignanello, the solitary name Vultasi doesn't help much to decide the matter. I can't help but appreciate too how, by using an unclear inscription, the author can quickly pass a shaky statement over the reader without being too obvious.
Luckily for us, TLE 651 does decide the matter. As pictured above, this is a statue of a standing nobleman nicknamed The Haranguer. The only names present in the entire inscription at the base of his toga are in the first line and they're declined in this same case: Auleśi Meteliś Ve. Vesial clenśi. Who would think that the image of this mystery man can be anything other than Aule Meteli himself? The inscription must read "For Aule Meteli, for the son of Vel and Vesi." If we interpret this case ending as by whom the statue is made, the inscription fails to explain who this man is while giving us useless information about the statue's creator. This data is hardly as important to an average, literate Etruscan as the man for whom all this metalworking effort was devoted!
Then too, we also find tinśi tiurim avilś χiś repeated several times in the Liber Linteus and since tin, tiur and avil are certain to mean 'day', 'month' and 'year' in these passages, forcing an agentive sense on an inanimate noun like tinśi is absurd. It must therefore mean 'for the day' in the context of the rituals to be performed on specified dates. An Etruscan agentive case has been concocted from nothing.
Bakkum goes on to write something that I'd gauge to be naive wording for a linguist:
"[...] in most other cases, the use of the -si or -(a)le form is due to a verb, usually mulu-."To observe that this case ending occurs often with the verb mulu- is justified, but to say that the use of this case marker is "due to" a verb, combined with his odd reference to Steinbauer above, seems to disqualify his expertise on structured grammar itself, let alone on Etruscan grammar. Need it be said, the use of this case ending or any case ending isn't incumbent on the verb itself per se but demanded by the overall semantics of what one is expressing. If one doesn't comprehend why -si/-le is used with some verbs like mulu- while not for other verbs, one fails to comprehend the very meaning of these individual grammatical units. The verbs haven't "caused" these endings to occur any more than the Oracle of Delphi.
The correct answer is simple: -si/-le must be consistently translated as 'for', as in 'for the purpose of' or 'on behalf of', never ever 'by' (whether in a locative or agentive sense). This value is evidenced not just in several Etruscan inscriptions but in Lemnian ones too.