नमस्ते हरमन्दर-सिंघ्-महोदय !
In the सूत्रम् - सोममर्हति यः (4'4'137) सोममर्हति is a complete sentence, an example sentence. It is an example sentence to explain use of the प्रत्यय यः, which seems to be a तद्धित प्रत्यय, helping to obtain an adjective सोम्य from the संज्ञा सोम.
If one should consider सोममर्हति as being one example, are there other examples ?
Comes to mind the word धर्म्य in गीता. It is an adjective derived from the noun धर्म. Meaning of धर्म्य and in turn of the तद्धित प्रत्यय यः seems to be अस्य अस्ति इति
(1) सोमः अस्य अस्ति इति सोम्य
(2) धर्मः अस्य अस्ति इति धर्म्य
References in गीता about धर्म्य are - (1) धर्म्याद्धि युद्धाच्छ्रेयोऽन्यत् क्षत्रियस्य न विद्यते (2'31) - (2) अथ चेत्त्विमं धर्म्यं संग्रामं न करिष्यसि (2'33) - (3) अध्येष्यते च य इमं धर्म्यं संवादमावयोः (18'70)
The प्रक्रिया here seems to be that ending अ of the respective प्रातिपदिक-s सोम, धर्म, gets dropped and the तद्धित प्रत्यय य affixes to the consonant left after dropping of अ. (1) सोम => सोम् => सोम् + य = सोम्य (2) धर्म => धर्म् + य = धर्म्य
I wonder whether गुण => गुण् + य = गुण्य also becomes a fitting example. Actually there is also a dhaatu गुण् and गुण्य can be its ण्यत्-कृदन्त. In Apte's dictionary I get गुण्य a. [गुण्-यत्] 1 Endowed with merits or virtues; गुण्यगुण्य इति न व्यजीगणत् Śi.14.47. -2 To be enumerated. -3 To be described or praised. -4 To be multiplied, the multiplicand.
Looking at the different meanings in the dictionary, I think the meaning "endowed with merits" is similar to अस्य अस्ति इति. If so this meaning is more in accordance with this सूत्रम् - सोममर्हति यः (4'4'137)
The other meanings "to be described or praised", to be multiplied, to be enumerated have passive voice inherent, which is an essential aspect of ण्यत्-कृदन्त.
So the word गुण्य merits to be considered as having two व्युत्पत्ति-s - (1) as ण्यत् / यत्-कृदन्त (2) by सूत्रम् - सोममर्हति यः (4'4'137). Accordingly the different meanings. Sounds good ?