In his "Literary Gleanings" published in The Quarterly Journal of the Andhra Historical Resarch Society 2/2, 1927, pp. 130-145, M. R. Kavi notes (I attach the relevant pages below) that one Buddhist Bāhyārthasiddhi is quoted in :1° the Prakaraṇapañcikā of Śālikanātha Miśra
[ch. 8, = Gretil input, 923-924 : api cāprakāśātmana eva prakāśas sambhavatīti bāhyārthasiddhāv uktam /
in fact there is a previous reference, 778 : nirākṛtaś cāyaṃ
bāhyārthasiddhāv ṛjuvimalāyām / — which one is misleading since the ṛjuvimalā is the title of Śālikanātha own commentary on Prabhākara's Bṛhatī]
2° [if I understand well] the Śarkarikā of "Bhaṭṭaputra" Jayamiśra (ed. Kunhan Raja, MUSS 17, 1946, not checked; which is a continuation of Umbeka's commentary on Kumārila's Ślokavārttika).
Could the so-referred work correspond to the
Bāhyārthasiddhi-kārikānāma of Śubhagupta preserved in Tibetan translation (a Sanskrit reconstructed text by N. A. Shastri [?< Bulletin of Tibetology 4, 1967?] is available on the DSBC :
http://www.dsbcproject.org/canon-text/titles/Bāhyarthasiddhikārikānāma-0 ) and recently dealt with
by M.S. Saccone ("Śubhagupta on the Cognitive Process") in the Journal of Indian Philosophy 42/2-3, 2014 pp. 377-399, and by H. Matsuoka (in the Journal of Indian and Buddhist Studies 61, 2013, pp. 1241-47) through its references in Śānta
rakṣita's Tattvasaṃgraha ?Thank you for any comment on this.
Best wishes,
Christophe Vielle