![Risk.net](https://www.risk.net/sites/default/files/styles/print_logo/public/2018-09/print-logo.png?itok=1TpHrpuP)
Professional investors behind ‘witching day’ options spike
Retail investors are the losers from anomaly that costs more than $3.8 billion
![data spike](/sites/default/files/styles/landscape_750_463/public/2024-02/GettyImages-1142272682.jpg.webp?h=7cb7abb5&itok=UdeTFNdu)
Researchers have added fuel to controversial claims made last year that equity index options may be subject to market manipulation.
The fresh analysis, which builds on work done by the same team in 2023, shows that professional investors benefit from a pricing anomaly in S&P 500 index options that costs retail investors more than $3.8 billion a year.
A study last September flagged an upwards jump in option prices on so-called witching days – the third Friday of the month, when many options
Only users who have a paid subscription or are part of a corporate subscription are able to print or copy content.
To access these options, along with all other subscription benefits, please contact info@risk.net or view our subscription options here: http://subscriptions.risk.net/subscribe
You are currently unable to print this content. Please contact info@risk.net to find out more.
You are currently unable to copy this content. Please contact info@risk.net to find out more.
Copyright Infopro Digital Limited. All rights reserved.
As outlined in our terms and conditions, https://www.infopro-digital.com/terms-and-conditions/subscriptions/ (point 2.4), printing is limited to a single copy.
If you would like to purchase additional rights please email info@risk.net
Copyright Infopro Digital Limited. All rights reserved.
You may share this content using our article tools. As outlined in our terms and conditions, https://www.infopro-digital.com/terms-and-conditions/subscriptions/ (clause 2.4), an Authorised User may only make one copy of the materials for their own personal use. You must also comply with the restrictions in clause 2.5.
If you would like to purchase additional rights please email info@risk.net
More on Investing
NAIC wants more disclosure about use of offshore reinsurance
US watchdog seeks improved data around deals some say allow insurers to game capital rules
Pre-market trades blamed for record Vix surge
Traders rushed to cover short vol positions before the market opened on August 5
The standoff over separate account margining
CFTC issues sixth extension of no-action relief as long-awaited final rule stalls
Can history resolve factor investors’ p-hacking questions?
Quants seek reassurance in the far distant past
Investors choose safer bank bonds as AT1 opportunity wanes
Technical factors mean senior bank bonds now offer relative value
Sliced and sliced again: investors’ latest trick for risk transfer
‘Retranched’ synthetic securitisations offer higher yields, but questions remain over legality of structures
After the selloff, competing theories on dealer gamma
Tier1 Alpha sees $74 billion short gamma catalyst; SG says rapid return to positive territory had calming effect
Corporate ‘greenium’ reveals effect of ESG rules on returns
Analysis of sustainable products shows how SFDR has caused a shift in investor behaviour, writes economist