In principle, the same rules apply to limited partnerships as to general partnerships – the partnership legally exists once it is registered with the state registry (usually Secretary of State) and once it begins trading.
If a limited partnership begins trading before having filed with the state registry, this can create a legal gray area for the limited partner. This is because their liability threshold is stated in their state register entry. Before the state register entry is made, the limited partner is considered a general partner, with their entire assets at stake, if the company is active but still unregistered. Confusion can also arise in limited partner liability if the capital contribution stated in the state register entry is higher than that agreed upon in the articles of association. In a debt situation, this could lead to the limited partner not having made their liability contribution in full, despite having paid the capital contribution. They would then be liable for the discrepancy between the two figures.
It is important to remember that each state in the USA has their own laws governing the formation of partnerships, so these regulations may not apply to your business. Please consult with your Secretary of State and a legal professional to ensure that your business is legally compliant.