Yes, yes and yes! Try google the concept of "piercing the corporate veil" and you will see that if you do not adhere to such formalities then your corporation will not protect you from the very liabilities you seek to ward off.....there is no lazy way to do this and in fact you should be scrupulous in your efforts to show the corporation is not your alter ego -- be forewarned here.
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Yes, as Mr Corrigan says it is important to observe corporate formalities in order to have your corporation respected as an entity. However, as a sole shareholder, this is probably not as onerous as it sounds. You do the bylaws one time, in most instances. You elect directors as provided in the bylaws (probably annually) and you document minutes for meetings or sign written actions in lieu of meetings. You can likely find templates for these documents on the internet.
As my colleagues answered, yes it is important and you need to observe corporate formalities in order to maintain corporate protection from any liabilities - otherwise the corporate veil can be pierced and you may personally be held liable.
The compliance requirements are not as bad as they sound. As Mr. Mohler stated, you do the bylaws once (unless in the future you want to make changes to them, then you can do amended bylaws and sign them). Make sure you sign them in your capacity as a corporate officer and keep them in a binder at the principal place of business. Usually you can do a consent to action in lieu of an organizational meeting and can do consents to action for items of action for the business. Keep copies of them in the binder with your bylaws and certificate of formation for the business. To maintain your corporate status, you will need to have an annual meeting. As with any other meetings, keep minutes of what actions were done at the meeting, sign the minutes and keep them in the binder.
If you don't have bylaws and need some, hire an attorney to draft bylaws for you. While there will be some expense, it may be well worth it to have bylaws for the corporation and get some other pointers from the attorney for corporate compliance and running the business.
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