Motions for summary judgment are once litigation is far along in its process, and motions to strike are filed against pleadings early on it litigation. You need to ask your own lawyer, who will have reviewed the operative complaint, whether either of those procedures are appropriate.
I'm not clear on how you could afford an offer of 2x the value of someone's shares, yet not be prepared to hire a lawyer. You have no choice here. Your company's been sued, and it can't defend itself, it can only act in court through its own lawyer. Use Avvo's "Find a Lawyer" search function, or use your family and/or friends for personal references, and hire a business litigator immediately. They can explain your options, and the relative strengths and weaknesses of your and your co-shareholder's claims. The 1st thing your lawyer should look at is any shareholder's agreement, and whether shareholders have agreed to arbitrate any disputes. If you can demand arbitration, rather than civil court, that would save money and time.
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A corporation or LLC cannot represent itself in court. Therefore, even a motion for summary judgment would have to be filed by a lawyer. This is not a wrongful lawsuit. In fact, the law provides for what is called "shareholder derivative" suits for violation of the terms of an operating agreement. You need an attorney to go over the alleged violation of the agreement and to evaluate your ex-partner's chance of success.
Your lawyer should evaluate the costs of litigation and how that factors into the decision to push forward to further litigation. Generally, a prudent company should have a legal defense fund available and insurance to cover most risk of liability. Our law firm does this type of business litigation and offers free consultations, so you could evaluate the costs before hiring.
Sorry, but your choices are to do whatever you can to get counsel or the corporation is in default. it is really that simple. As to not having money for counsel, there are three other shareholders. They can't pool to pay an attorney? If this matters at all, they will do what they can to pay or lose. Good luck.
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