(a) A holder of or subscriber for shares of a corporation shall be under no obligation to the corporation for payment for such shares other than the obligation to pay the unpaid portion of his subscription which in no event shall be less than the amount of the consideration for which such shares could be issued lawfully.

(b) Any person becoming an assignee or transferee of shares or of a subscription for shares in good faith and without knowledge or notice that the full consideration therefor has not been paid shall not be personally liable for any unpaid portion of such consideration, but the transferor shall remain liable therefor.

(c) No person holding shares in any corporation as collateral security shall be personally liable as a shareholder but the person pledging such shares shall be considered the holder thereof and shall be so liable. No executor, administrator, guardian, trustee or other fiduciary shall be personally liable as a shareholder, but the estate and funds in the hands of such executor, administrator, guardian, trustee or other fiduciary shall be liable.