PDF SOLUTIONS INC

Ticker: PDFS CUSIP: 693282105 Class: Common Stock

Yorktown Management & Research Co Inc's Holding History (CIK: 0001313559)

Note: Option positions (PUT/CALL) are excluded.

Q1 2014

Shares 10,800 Value ($000) $196 Avg Close $22.07 Range $17.21 - $26.73

Q4 2013

Shares 10,800 Value ($000) $277 Avg Close $22.99 Range $20.12 - $25.90

Q3 2013

Shares 16,500 Value ($000) $351 Avg Close $20.57 Range $18.09 - $22.20

Q2 2013

Shares 16,500 Value ($000) $304 Avg Close $17.41 Range $14.95 - $19.03

Period	Shares	Value ($000)	Average Close	Price Range
Q1 2014	10,800	$196	$22.07	$17.21 - $26.73
Q4 2013	10,800	$277	$22.99	$20.12 - $25.90
Q3 2013	16,500	$351	$20.57	$18.09 - $22.20
Q2 2013	16,500	$304	$17.41	$14.95 - $19.03