|Date of birth||10 June 1989|
|Place of birth||Stockton-on-Tees, Cleveland|
|Height||1.93 m (6 ft 4 in)|
|Weight||111 kg (17 st 7 lb; 245 lb) |
|School||Barnard Castle School|
|Rugby union career|
The flanker racked up 23 appearances in his debut season at Leeds and was called up to the England U20s in 2008. Clark helped the national side to the 2008 IRB Junior World Championship (JWC) final and was back in the side the following season, this time as captain for both the Six Nations tournament and the JWC campaign where he led England to the final again.
Now a veteran at the Saints, Clark spent much time out for various injuries but most recently spent a sustained period out for a shoulder injury he received in Saints' preseason friendly against Wasps in October 2015. The flanker returned to play for the Saints senior side on 30 September 2016 as the Midlands side beat Exeter Chiefs 20-19 and then went on to score his first try of the 2016/17 season against Montpellier Herault Rugby on 15 October.
In 2012, Clark was banned for 32 weeks for deliberately hyper-extending the arm of Leicester Tigers hooker Rob Hawkins causing a fractured elbow. Such an offence could attract an entry point of 5 years, however, the disciplinary panel found that whilst the offence itself was intentional, there was no evidence that Clark intended to cause a serious injury. Although, many believe he should not be allowed to play rugby again due to his disgraceful actions. 
- Calum Clark. "Calum Clark". Northamptonsaints.co.uk. Archived from the original on 12 March 2012. Retrieved 23 February 2012.
- "Archived copy". Archived from the original on 9 May 2013. Retrieved 10 May 2013.CS1 maint: archived copy as title (link)
- "Aviva Premiership Rugby - Northampton Saints". web page. Premier Rugby. Archived from the original on 2 February 2012. Retrieved 21 September 2011.
- "Archived copy". Archived from the original on 29 May 2016. Retrieved 21 October 2016.CS1 maint: archived copy as title (link)
- http://www.northampton-news-hp.co.uk/northampton-saints-no-return-date-set-for-long-term-injury-victim-calum-clark/story-29536888-detail/story.html[permanent dead link]
- "Northampton Saints flanker Calum Clark given 32-week ban". BBC Sport. 30 March 2012. Retrieved 29 October 2016.
- "RFU Disciplinary Judgement Calum Clark" (PDF).
- "Premiership final: Saracens 20-24 Northampton Saints". 31 May 2014. Retrieved 24 March 2019 – via www.bbc.co.uk.
- "Saracens sign Northampton Saints and former England flanker Calum Clark". BBC Sport. 17 January 2017. Retrieved 17 March 2017.
- "England announce Rugby World Cup training group". englandrugby.com. 20 May 2015. Retrieved 1 March 2016.
- "England beat France 19-14 in Rugby World Cup warm-up". BBC Sport. 15 August 2015. Retrieved 1 March 2016.