Board sanction required for director related contracts; noncompliance renders transactions voidable and urgent deals need prompt board approval. Section 297 requires board sanction for contracts between a company and interested directors, relatives, partner-firms, partners or private companies for sale, purchase, supply of goods, materials or services and for underwriting. Exceptions cover cash market-price transactions, routine trading relationships within a small annual value, and ordinary course dealings by banks and insurers. Urgent contracts may be entered into without prior consent but must receive board approval at a meeting within three months; board consent must be by resolution and, if withheld, renders the contract voidable at the board's option.