PASS Securities Operations and Risk Management Examination Difficulty: Beginner 2 Questions   5 min read
📌 Chapter 6.5 — AUCTION OF SECURITIES

Consider a high-pressure morning where your firm is executing a block deal worth INR 50 crores for an institutional client. Unlike standard retail orders that flow through the regular order book, a block deal occurs in a dedicated window where the buyer and seller are pre-identified. As an operations professional, your immediate concern is the settlement cycle, which operates on a T+1 basis, mirroring the standard market, but with significantly higher stakes regarding the integrity of the delivery.

The trade is executed at a specific price, and the clearing process requires both parties to have their obligations ready within the strict deadlines mandated by the clearing corporation.

When a securities shortage occurs in a block deal, the mechanism deviates from the standard retail auction. Because block deals are distinct, the system typically mandates that the clearing corporation handles the failure through a process designed to isolate the impact.

If the seller fails to deliver the promised quantity by the pay-in deadline, the clearing house will not simply dump the transaction into the standard retail auction pool, as that would cause significant price distortion for such a large quantity. Instead, the focus shifts to direct financial compensation or, where feasible, an enforced market buy-in specific to that block.

You must ensure that your firm’s internal controls are robust enough to flag potential shortfalls before the block window closes. If you are representing the buyer, you are monitoring for the credit of securities into your pool account; if the seller defaults, your firm remains exposed to the market price volatility until the clearing corporation resolves the breach. This is why risk management teams often require 100% pre-trade margin in the form of cash or liquid collateral for these transactions.

Unlike small retail errors, a failure in a block deal can attract heavy regulatory scrutiny and potential penalties from the exchange due to the sheer size of the transaction.

Ultimately, managing a block deal is about transparency and timing. Always verify that the client has the necessary holdings in their demat account before the order is placed, as standard internal shortages cannot be easily ’netted’ out in these high-value segments. Treat every block deal as a potential point of systemic stress, and ensure your reconciliation team is prepared to handle the unique settlement instructions provided by the exchange for these large-scale trades.

Nuance

⚠️ Nuance
A common misconception among candidates is that block deals follow the same auction rules as retail trades for all types of shortages. In reality, the clearing corporation often exercises discretion or uses specialized close-out procedures for block deals to prevent market impact costs from spiraling. Candidates often fail to distinguish between the ‘regular’ market auction and the institutional settlement protocols, assuming that any default simply flows into the next day’s general auction bucket.

Check Your Understanding

Practice Question 1

In the event of a securities shortage in a block deal settlement, which of the following is the primary operational priority for the clearing corporation?

Practice Question 2

Why are pre-trade margin requirements typically more stringent for block deals compared to standard retail orders?

This is a companion read for Section 6.5 — AUCTION OF SECURITIES from PASS Securities Operations and Risk Management Examination by Akhilesh Gururani, available on Amazon Kindle.

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