I am starting this clean thread so we don't have to plow through 2005 issues. As best I understand, your' question is:
In the area where it reads: IN WITNESS WHEREOF, the parties hereto have executed the foregoing agreement upon the understanding that it shall become effective on ________, 19_______. (This was NEVER Filled out)
I signed it with my date. A general principal (Sign Stamped) it one week later.
I did not start with the firm until 3 and a half months later. Since the IN WITNESS WHEREOF was Never dated and the delay of starting with the firm and another contact was not signed: Is this a valid contract? This contract was from 1993!
First off, I don't understand what you mean that you "signed it with my date." Did you add a date to indicate the "effective" date or do you simply mean that you dated your signature?
Similarly, one would need to read the agreement, but a contract can become "effective" before an employee/consultant begins employment. The 3 1/2 month delay may have a material impact on some aspects of this issue, but it would not be unusual for someone to negotiate a deal that becomes effective upon signing and then, say, give a few months of notice to the current employer. Hope that explains the disconnect between an effective and a start date.
Whether or not your specific contract will be upheld a valid will depend upon a number of issues. Firstly, the mere absence of a date may or may not be deemed "material" to the contract. If the omission is deemed immaterial, then the contract may well be enforceable. If the omisison is deemed a material one, then the contract may be ruled invalid. Unfortunately, there is no simple answer to that question and that may well be an issue for an arbitration panel to decide.
However, much will likely be made of the fact that you signed the agreement and apparently "thought" you were subject to it. Your former employer may well argue that you should be estopped from claiming that you were not subject to the agreement because you signed it and began employment under its terms (oral or written, as it were).
Separately, I do not know whether this 1993 written agreement contained a "term." Are you suggesting that the term expired prior to your leaving?
Finally, in sustaining non-competes/non-solicits, the law tends to favor that such restrictions be in writing and in clear terms and in an enforceable agreement. The case you present has equities on both sides and you should at least be thankful that you do not have a "clean" document that can be presented against you. The omission, whether material or not, gives you quite a bit more to work with than most folks in your position.
Ultimately, if you choose to fight, you will likely find a lawyer who will be able to do something with the omission you note. I cannot tell you that such legal footwork will get you out of any stated obligations, but depending how your case is argued, you may achieve that result -- on the other hand, if there is a chance of settlement, the deficiency should prompt your employer to offer more liberal terms. One thing your lawyer should seek during limited discovery are copies of all such agreements during the relevant timeframe for which the referenced date was not filled in. If there is a very small sample, you may well argue that the omission in your document is rare, that the firm was put on notice by this unusual omission that the agreement would be challenged as invalid, and, perhaps, that the firm should not now benefit from its own negligence in failing to obtain fully executed agreements.
Does that help?