Based on the provided legal document, here are the key legal points:

1. The auction conducted by the Tahsildar was found to be invalid due to non-compliance with mandatory statutory provisions, specifically the requirement of a 30-day notice period before the auction. Conducting the auction prematurely and issuing the sale certificate without proper confirmation violated the relevant procedures (!) (!) .

2. The sale was confirmed before the expiry of the statutory notice period, and possession was handed over to the purchaser prior to formal confirmation by the competent authority, rendering the sale illegal. The sale process did not adhere to the procedural requirements laid down for auction sales under the Revenue Code (!) (!) (!) .

3. The sale certificate was issued on the same day as the auction, and possession was transferred before the sale was formally confirmed, which is contrary to the statutory provisions that require confirmation and issuance of the sale certificate after the sale proceeds are received and the sale is validated (!) .

4. There was suppression of objections received from a financial institution (IFCI) regarding the mortgage and sale process, which indicates collusion and mala fide conduct by the Tahsildar and other officials involved (!) (!) .

5. The valuation of the property and machinery was manipulated to favor the appellant, including undervaluation of machinery and improper valuation of immovable property, further indicating collusive and fraudulent conduct (!) (!) .

6. The auction notice did not comply with the mandatory 30-day notice period, and the auction was held in breach of statutory provisions, which require such notice to ensure transparency and fairness (!) (!) (!) .

7. The process of confirmation and sale was hurried and illegal, with sale confirmation occurring before the statutory period for objections had elapsed, and possession was transferred before formal confirmation, violating specific procedural provisions (!) .

8. The appellate authority (Additional Commissioner) lacked jurisdiction to entertain the appeals filed by the respondent nos. 1 and 6, as the remedies available under the Revenue Code (Sections 210 and 247) were not properly exhausted or were inapplicable in the circumstances. Nonetheless, the order passed by the appellate authority was not disturbed, as doing so would revive the illegal sale (!) (!) .

9. The courts emphasized that in cases questioning the legality of auction proceedings, especially involving public authorities, the focus should be on ensuring fairness, transparency, and compliance with mandatory legal provisions. The courts are cautious in interfering with auction sales unless there is clear evidence of mala fide conduct, gross illegality, or violation of statutory procedures that go to the root of the matter (!) (!) (!) .

10. The court recognized that the proceedings under the Revenue Code should be distinguished from judicial proceedings under civil law, and the principles of procedural irregularities and fraud require strict proof of substantial injury caused by such irregularities before the sale can be invalidated (!) (!) .

11. The court permitted the appellant to deposit a substantial amount (Rs. 4 crore) within a specified period to settle liabilities and avoid further sale or dispossession, balancing the need for justice with practical considerations of ongoing industrial activity and employment (!) (!) .

12. Overall, the courts underscored that auction proceedings conducted in violation of mandatory statutory provisions, especially those designed to ensure fairness and transparency, are inherently illegal and cannot be validated merely on the basis of irregularities unless substantial injury is established and procedural violations are proven to have caused such injury (!) (!) .

These points collectively highlight the importance of strict adherence to legal procedures in public auction sales, the need for transparency, and the courts’ cautious approach in cases involving alleged procedural violations and collusion.