doctrine of ultra vires

can you elaborate your question as to what ultra vires what?

No, shareholders can't ratify the ultra vires act (Ultra vires to MOA) of Directors though company availed benefit out of such act.

Here you must understand that what is ultra Vires act under companies Act, 2013. Here it is-
Act/ Transaction of company or director,
1. which is not permitted or authorized by Companies Act, 2013.
2. Which falls outside the objects clause of MOA.

To reply your point.
Though Shareholders ratify this, ultra vires act can't become valid. Since UV act doesn't create legal relationship between company and outsiders as debtors and creditors, Directors are personally liable for that.

actually directors are not liable because company assumes that whoever does transection with company they have already read the Memorandum of Association.

That is Doctrine of Indoor management. Not Doctrine of Ultra Vires

sorry it was my mistek,if the act is ultra vires to directors power it can be ractify by members at general meeting and once it is ractified the directors are not liable.

If the act is ultra vires to memorandum it can't be ractified and directors are personally liable because the directors can't have powers over and above the Memorandum of Association.

What is ultra vires to Directors power.? There is no such thing in Co law

when director acts beyond their authority,it would be construed as ultra vires to directors powers.

Powers of board you can understood by reading section 179 to Section 195 of companies Act and the rules made thereunder.

I have read those span of sections and never ever read such thing called Ultra vires to Directors powers.

Directors are authorized to act according to provisions of companies Act, 2013 and MOA (certain cases required authorization of Shareholders). If anything beyond the MOA will amount to Ultra Vires to MOA, Not ultra vires to Powers of Directors.

Can you please give me any examples for ultra vires to Directors powers? And
Can you give any reference to prove the concept called Ultra Vires to Directors powers? Where it is mentioned?
Any doctrines? Any provisions? Any caselaws?

don't show ever

For example,as you said,in curtain cases directors requires authorisation of share holders.

In those cases if director acts without authorisation of shareholder,then it would be called Ultra Vires to Director's Powers.