The main point of departure for any inquiry into Dignāga’s theory of apoha is his Pramāṇasamuccaya, chapter 5. Unluckily enough, this text is only available as a reconstruction from the two (divergent) Tibetan translations and from Jinendrabuddhi’s commentary.

Kei Kataoka, Ole Holten Pind and Kiyotaka Yoshimizu have disagreed on how to reconstruct the sequence of opponents and siddhantin in PS 5. In the following, I will deal with 5.41–42 and I will only add some furhter questions to the ones they have listed already, in the vague hope that clear questions contribute more than dogmatic answers to the advancement of a discipline.

Let me start with PS 5.41ab. Here Dignaga has:

sāsnādidarśanād gopratyayaḥ.

Who is speaking here? To whom should this view be attributed?
Jinendrabuddhi starts his commentary with:

tatra hi vaibhā{g}ikenoktam (see below for the uncertainties concerning this reading)

Pind and Yoshimizu consequently attribute PS 5.41ab to a certain “Vaibhāgika”, whereas Kataoka attributes it to the Sāṅkhya Mādhava, who would there be rephrasing Dignāga’s view.
In favour of his view, Kataoka can point to the fact that the Tibetan translation of Jinendrabuddhi’s commentary does not have tatra hi vaibhāgikenoktam but rather translates *vaināśikena, which could refer to Mādhava’s fame of “destroyer” of the Sāṃkhya system. Furthermore, vaibhāgika would be an absolute hapax. Last, Kataoka kindly informed me (and the audience at the IDhK conference in Heidelberg) that the manuscript of the Sanskrit version of Jinendrabuddhi, which would be the only evidence in favour of vaibhāgikena, does not clearly confirm it.

Jinendrabuddhi then adds:

atra sāṅkhyena pratividhānam āha

This is a univocal reference to a Sāṅkhya author, possibly Mādhava. If Kataoka is right, both passages are then attributed to Mādhava, but the first one is a rephrasal of Dignāga by Mādhava, whereas the second is Mādhava’s critique to Dignāga.

Last should come Dignāga’s reply. But where does it exactly start?

PS 5.41–42 read as follow in Pind’s reconstruction:

sāsnādidarśanād gopratyayaḥ yo ‘yam udāhṛtaḥ |
so viruddho bhavanmatyā bhinnāpohyas tu te mithaḥ || 41 ||
so ‘napekṣa ity etat tu svavikalpavirmitam |
nirapoham […] || 42 ||

Kataoka:
sāsnādidarśanād gopratyayaḥ: Mādhava
yo ‘yam udāhṛtaḥ so viruddho, bhavan[=Sāṅkhya]matyā, bhinnāpohyas tu te mithaḥ: Dignāga. bhavanmatyā is not connected to viruddhaḥ and it means that the example has been only provisionally introduced from the point of view of Sāṅkhya. 41d is Dignāga’s authentic siddhānta, which follows in v.42.

Yoshimizu:
sāsnādidarśanād gopratyayaḥ: Vaibhāgika
so ‘yam udāhṛtaḥ so viruddho, bhavan[=Dignāga’s]matyā: Mādhava’s criticism of Dignāga
bhinnāpohyas tu te mithaḥ: Mādhava
Yoshimizu thus stresses the importance of the tu as indicating a change of speaker.
v. 42: Dignāga. Again, the tu is stressed as the key element to understand that a new discussant is now speaking.

If Kataoka is right, Dignāga only provisionally accepted that one grasps a cow by means of dew-lap etc., whereas in fact he never moved from the absolute exclusive/negative nature of the apoha theory, which does not admit any positive entity, be it a cow or a dew-lap.

If Yoshimizu (or Pind, since if I am not wrong their views tend to be quite close) is right, Dignaga does indeed accept that one grasps a cow by means of a dewlap, etc. (Yoshimizu suggested in his 2011 article discussed here that this implies a componential analysis and not the real existence of dew-lap, etc.).

These are only my reconstructions of Pind’s, Yoshimizu’s and Kataoka’s thought as represented in, respectively, Pind’s PhD thesis, Yoshimizu’s paper discussed here and Kataoka’s papers presented at the last IABS and IDhK conferences. All mistakes are mine.