In Jain Dharma, marriage rules about how close a blood‑relation can be are mostly a matter of society, family custom, and the civil law of your country, not detailed Jain scriptural rules.

A few simple points:

1. Jain scriptures

- They mainly stress that a life‑partner should be satvik, virtuous, follow ahiṁsā, truth, good conduct, and help in spiritual progress. - They do not give a detailed chart like “up to which generation you can marry.”

1. Close‑relative marriage

- In almost all Jain communities, marriage with close blood relatives is avoided (for example, those counted in the same “kul” or very near generations). - Many families follow the general Indian custom: do not marry where there is a close common ancestor, especially on the father’s side and often on the mother’s side too. - This is seen as part of proper social conduct (samācār) and also for health reasons.

1. “4th generation” point

- Different families count “generation” differently (sometimes from you, sometimes from a common ancestor). - Some communities avoid marriage as long as there is a clear living memory of common great‑grandparents or their siblings, i.e., they stay on the safer side and do not marry even if technically allowed. - So whether “4th generation” is acceptable in your case depends on how your community counts it and what the law allows – not on a specific Jain śāstra verse.

1. Practical Jain guidance

- Make sure the match is not a close blood relation according to: - your country’s marriage law, and - your Jain community’s rules (gotra/kul, etc.). - Also ensure both follow Jain values (ahiṁsā in food, honesty, avoiding addictions, etc.).

So, from Jain Dharma side:

• There is no fixed rule like “you can/cannot marry till 4th generation” written in scriptures.
• But marrying close blood relatives is generally avoided and discouraged; follow local law and your Jain community’s accepted norms to stay within dhārmik and social maryādā.