Exhibit 99.1

Investor Contact:                         Media Contact:

Nicole Vattimo                            Dana Grosser

SEI    SEI

+1 610-676-4385                        +1 610-676-2459

nvattimo@seic.com                         dgrosser@seic.com

Pages:        9

FOR IMMEDIATE RELEASE

SEI REPORTS THIRD-QUARTER 2013 FINANCIAL RESULTS

OAKS, Pa., October 24, 2013 -- SEI Investments Company (NASDAQ:SEIC) today announced financial results for third-quarter 2013. Diluted earnings per share were $.38 in third-quarter 2013 compared to $.29 in third-quarter 2012.

Consolidated Overview		For the Three Months											For the Nine Months
(In thousands, except earnings per share)		Ended September 30,											Ended September 30,
		2013				2012				%			2013				2012				%
Revenues		$	280,655			$	251,752			11	%		$	827,108			$	730,887			13	%
Net Income attributable to SEI		67,195				50,743				32	%		222,609				150,263				48	%
Diluted Earnings Per Share			$0.38				$0.29			31	%			$1.26				$0.85			48	%

"During the third quarter of 2013, the Company continued its positive progress across all of our business units. Our growth in revenues and profits reflect the impact of new client activity, growth of existing clients, and positive asset flows," said Alfred P. West, Jr., SEI Chairman and CEO.

“We continue to be encouraged by the market acceptance of our solutions. We are engaged in rapidly-changing markets requiring continued investment in our product and service offering. This enables us to enhance our competitive strength, accelerate our growth, and enhance long-term shareholder value.”

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Summary of Third-Quarter Results by Business Segment

(In thousands)		For the Three Months											For the Nine Months
		Ended September 30,											Ended September 30,
		2013				2012				%			2013				2012				%
Private Banks:
Revenues			$97,370				$92,076			6	%			$291,258				$268,367			9	%
Expenses		95,579				91,209				5	%		289,632				263,612				10	%
Operating Profit		1,791				867				107	%		1,626				4,755				(66	)%
Gain on sale of subsidiary		—				—				N/M			22,112				—				N/M
Total Profit			$1,791				$867			107	%			$23,738				$4,755			N/M
Operating Margin (A)		2		%		1		%					1		%		2		%
Investment Advisors:
Revenues		61,393				51,384				19	%		175,868				150,227				17	%
Expenses		33,768				30,114				12	%		98,291				88,440				11	%
Operating Profit		27,625				21,270				30	%		77,577				61,787				26	%
Operating Margin		45		%		41		%					44		%		41		%
Institutional Investors:
Revenues		63,539				58,081				9	%		190,385				167,293				14	%
Expenses		33,058				29,654				11	%		97,595				86,494				13	%
Operating Profit		30,481				28,427				7	%		92,790				80,799				15	%
Operating Margin		48		%		49		%					49		%		48		%
Investment Managers:
Revenues		57,266				49,311				16	%		166,542				142,235				17	%
Expenses		37,763				32,122				18	%		109,432				92,711				18	%
Operating Profit		19,503				17,189				13	%		57,110				49,524				15	%
Operating Margin		34		%		35		%					34		%		35		%
Investments in New Businesses:
Revenues		1,087				900				21	%		3,055				2,765				10	%
Expenses		4,146				3,698				12	%		11,774				11,080				6	%
Operating Loss		(3,059		)		(2,798		)		N/M			(8,719		)		(8,315		)		N/M
Totals:
Revenues		$	280,655			$	251,752			11	%		$	827,108			$	730,887			13	%
Expenses		204,314				186,797				9	%		606,724				542,337				12	%
Corporate overhead expenses		14,402				11,668				23	%		40,719				33,830				20	%
NCI reflected in segments		—				(203		)		N/M			(289		)		(657		)		N/M
Income from operations		$	61,939			$	53,490			16	%		$	179,954			$	155,377			16	%

(A) Percentage determined exclusive of gain on sale of subsidiary.

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Third-Quarter Business Commentary:

•	Revenues increased in third-quarter 2013 as compared to both third-quarter 2012 and second-quarter 2013. Revenue growth was primarily driven by higher Asset management, administration, and distribution fees from improved cash flows from new and existing clients and market appreciation.

•

Our average assets under management, excluding LSV, increased $11.3 billion, or nine percent, to $143.9 billion in the third-quarter 2013, as compared to $132.6 billion during the third-quarter 2012, and increased $3.0 billion, or two percent, as compared to $140.9 billion during the second-quarter 2013. Average asset balances for the third-quarter 2012 include $6.5 billion in assets related to SEI Asset Korea, which was sold in first-quarter 2013 (see attached Ending and Average Asset Balances schedules for further details).

•	Sales events, net of client losses, during third-quarter 2013 totaled approximately $20.7 million and are expected to generate net annualized recurring revenues of approximately $18.3 million when contract values are fully realized.

•	Income from LSV increased in third-quarter 2013 to $31.3 million as compared to $24.9 million in third-quarter 2012 due to an increase in assets under management. Our ownership interest in LSV was approximately 39.3 percent in third-quarter 2013 and 39.8 percent in third-quarter 2012.

•

Stock-based compensation expense in third-quarter 2013 increased by $7.2 million as compared to third-quarter 2012. This incremental expense reflects a change in our estimate of the timing of when stock option vesting targets will be achieved. The Private Banks segment recognized $2.1 million of this incremental expense. The Investment Advisors, Institutional Investors, and Investment Managers segments each recognized approximately $1.3 million in expense.

•	Corporate overhead costs increased in third-quarter 2013 as compared to third-quarter 2012 due to $1.2 million in increased stock-based compensation, increased personnel costs, and higher costs related to regulatory and compliance matters.

•

The effective tax rates were 28.5 percent in third-quarter 2013, 39.0 percent in third-quarter 2012, and 35.5 percent in second-quarter 2013. The third-quarter 2013 tax rate was benefited by Pennsylvania Tax Law changes enacted during the third-quarter 2013. These changes resulted in a reduction of the deferred tax liability that has been built up over numerous years. The third-quarter 2012 tax rate reflected the accrual of taxes on the cumulative undistributed earnings of SEI Asset Korea.

•	In third-quarter 2013, we repurchased 1.9 million shares of our common stock for $58.6 million.

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Earnings Conference Call

A conference call to review earnings is scheduled for 2:00 p.m. ET on October 24, 2013. Investors may listen to the call at www.seic.com/investors. The call may also be accessed at the financial services sections of numerous web sites, including Google Finance and Yahoo Finance. Investors may also listen to replays at these web sites, or by telephone at (USA) 1-800-475-6701; (International) 320-365-3844, access code 306035.

About SEI

SEI (NASDAQ:SEIC) is a leading global provider of investment processing, fund processing, and investment management business outsourcing solutions that help corporations, financial institutions, financial advisors, and ultra-high-net-worth families create and manage wealth. As of September 30, 2013, through its subsidiaries and partnerships in which the company has a significant interest, SEI manages or administers $529 billion in mutual fund and pooled or separately managed assets, including $219 billion in assets under management and $310 billion in client assets under administration. For more information, visit www.seic.com.

Many of the statements in this release may be considered “forward looking statements” and include discussions about future operations, strategies and financial results. Forward-looking statements are based upon estimates and assumptions that involve risks and uncertainties, many of which are beyond our control or are subject to change. Although we believe our assumptions are reasonable, they could be inaccurate. Our actual future revenues and income could differ materially from our expected results. We have no obligation to publicly update or revise any forward-looking statements.

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SEI INVESTMENTS COMPANY

CONSOLIDATED STATEMENTS OF OPERATIONS

(In thousands, except per share data)

(Unaudited)

		For the Three Months Ended September 30,
		2013				2012
Asset management, admin. and distribution fees			$208,780				$183,083
Information processing and software servicing fees		64,606				60,901
Transaction–based and trade execution fees		7,269				7,768
Total revenues		280,655				251,752
Subadvisory, distribution and other asset mgmt costs		31,209				26,022
Software royalties and other information processing costs		7,541				6,701
Brokerage commissions		5,519				5,542
Compensation, benefits and other personnel		89,311				85,781
Stock-based compensation		11,097				3,879
Consulting, outsourcing and professional fees		33,367				27,314
Data processing and computer related		12,654				11,749
Facilities, supplies and other costs		13,573				15,129
Amortization		8,829				10,384
Depreciation		5,616				5,761
Total expenses		218,716				198,262
Income from operations		61,939				53,490
Net gain on investments		535				3,708
Interest and dividend income		679				1,490
Interest expense		(195		)		(115		)
Equity in earnings of unconsolidated affiliates		31,028				24,928
Net income before income taxes		93,986				83,501
Income taxes		26,791				32,415
Net income		67,195				51,086
Less: Net income attributable to the noncontrolling interest		—				(343		)
Net income attributable to SEI			$67,195				$50,743
Diluted earnings per common share			$0.38				$0.29
Shares used to calculate diluted earnings per share		176,043				175,369
Basic earnings per common share			$0.39				$0.29
Shares used to calculate basic earnings per share		171,308				173,429

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SEI INVESTMENTS COMPANY

CONSOLIDATED STATEMENTS OF OPERATIONS

(In thousands, except per share data)

(Unaudited)

		For the Nine Months Ended September 30,
		2013				2012
Asset management, admin. and distribution fees			$611,135				$532,650
Information processing and software servicing fees		191,606				174,355
Transaction–based and trade execution fees		24,367				23,882
Total revenues		827,108				730,887
Subadvisory, distribution and other asset mgmt costs		88,795				79,442
Software royalties and other information processing costs		22,912				19,337
Brokerage commissions		18,291				17,483
Compensation, benefits and other personnel		264,636				244,855
Stock-based compensation		26,997				11,777
Consulting, outsourcing and professional fees		98,667				80,598
Data processing and computer related		37,028				34,873
Facilities, supplies and other costs		47,280				44,909
Amortization		25,498				25,413
Depreciation		17,050				16,823
Total expenses		647,154				575,510
Income from operations		179,954				155,377
Net gain on investments		638				7,577
Interest and dividend income		2,420				4,417
Interest expense		(422		)		(389		)
Equity in earnings of unconsolidated affiliates		86,204				74,970
Gain on sale of subsidiary		22,112				—
Other income		43,429				—
Net income before income taxes		334,335				241,952
Income taxes		111,376				90,892
Net income		222,959				151,060
Less: Net income attributable to the noncontrolling interest		(350		)		(797		)
Net income attributable to SEI			$222,609				$150,263
Diluted earnings per common share			$1.26				$0.85
Shares used to calculate diluted earnings per share		176,036				176,317
Basic earnings per common share			$1.29				$0.86
Shares used to calculate basic earnings per share		172,043				174,869

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SEI INVESTMENTS COMPANY

CONDENSED BALANCE SHEETS

(In thousands)

(Unaudited)

		September 30,				December 31,
		2013				2012
Assets
Cash and cash equivalents			$527,214				$452,247
Restricted cash		5,500				6,000
Receivables, net		225,961				202,818
Securities owned		20,728				20,088
Other current assets		20,629				20,251
Total current assets		800,032				701,404
Property and equipment, net		118,494				127,581
Investments available for sale		86,186				75,869
Trading securities		4,841				5,909
Capitalized software, net		313,206				307,490
Investment in unconsolidated affiliates		57,429				77,398
Other assets, net		11,511				14,173
Total assets			$1,391,699				$1,309,824
Liabilities
Current liabilities			$145,278				$152,005
Deferred income taxes		71,151				93,458
Other Long-term liabilities		8,703				7,032
Total SEI Investments Company shareholders’ equity		1,166,567				1,038,180
Noncontrolling interest		—				19,149
Total Equity		1,166,567				1,057,329
Total liabilities and equity			$1,391,699				$1,309,824

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SEI INVESTMENTS COMPANY

ENDING ASSET BALANCES

(In millions)

(Unaudited)

			Sept. 30,				Dec. 31,				Mar. 31,				Jun. 30,				Sept. 30,
			2012				2012				2013				2013				2013
Private Banks:
Equity/Fixed Income programs				$17,960				$18,862				$12,446				$12,876				$14,305
Collective Trust Fund programs			147				11				9				10				11
Liquidity funds			5,342				6,008				5,143				5,048				5,167
Total assets under management				$23,449				$24,881				$17,598				$17,934				$19,483
Client assets under administration			11,611				12,178				12,970				13,122				14,101
Total assets				$35,060				$37,059				$30,568				$31,056				$33,584
Investment Advisors:
Equity/Fixed Income programs				$30,864				$31,220				$34,166				$34,447				$36,203
Collective Trust Fund programs			370				14				15				14				14
Liquidity funds			1,868				2,514				2,094				2,145				2,779
Total assets under management				$33,102				$33,748				$36,275				$36,606				$38,996
Institutional Investors:
Equity/Fixed Income programs				$59,852				$62,160				$64,214				$61,927				$64,429
Collective Trust Fund programs			153				102				101				106				107
Liquidity funds			3,272				2,454				2,810				2,901				3,125
Total assets under management				$63,277				$64,716				$67,125				$64,934				$67,661
Investment Managers:
Equity/Fixed Income programs				$65				$67				$73				$75				$75
Collective Trust Fund programs			15,433				16,197				17,656				18,197				19,868
Liquidity funds			396				408				522				542				678
Total assets under management				$15,894				$16,672				$18,251				$18,814				$20,621
Client assets under administration (A)			240,965				244,671				275,632				289,807				295,959
Total assets				$256,859				$261,343				$293,883				$308,621				$316,580
Investments in New Businesses:
Equity/Fixed Income programs				$534				$513				$552				$572				$594
Liquidity funds			29				43				42				29				26
Total assets under management				$563				$556				$594				$601				$620
LSV Asset Management:
Equity/Fixed Income programs				$58,886				$60,947				$64,958				$65,417				$71,149
Total:
Equity/Fixed Income programs (B) (D)				$168,161				$173,769				$176,409				$175,314				$186,755
Collective Trust Fund programs			16,103				16,324				17,781				18,327				20,000
Liquidity funds			10,907				11,427				10,611				10,665				11,775
Total assets under management				$195,171				$201,520				$204,801				$204,306				$218,530
Client assets under administration (C)			252,576				256,849				288,602				302,929				310,060
Total assets				$447,747				$458,369				$493,403				$507,235				$528,590

(A)	Client assets under administration in the Investment Managers segment include $56.2 billion of assets balances that require limited services and therefore are at fee levels below our normal full service assets (as of Sept. 30, 2013).

(B)	Equity/Fixed Income programs include $3.9 billion of assets invested in various asset allocation funds at Sept. 30, 2013.

(C)	In addition to the numbers presented, SEI also administers an additional $5.6 billion in Funds of Funds assets (as of

Sept. 30, 2013) on which SEI does not earn an administration fee.

(D)	Equity/Fixed Income programs in the Private Banks segment for 2012 included assets related to SEI Asset Korea, which was sold in first-quarter 2013. Assets for SEI Asset Korea at Sept. 30, 2012 and Dec. 31, 2012 were $6.6 billion and $7.0 billion, respectively.

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SEI INVESTMENTS COMPANY

AVERAGE ASSET BALANCES

(In millions)

(Unaudited)

			3rd Qtr.				4th Qtr.				1st Qtr.				2nd Qtr.				3rd Qtr.
			2012				2012				2013				2013				2013
Private Banks:
Equity/Fixed Income programs				$17,527				$18,301				$19,197				$12,959				$13,696
Collective Trust Fund programs			230				66				11				10				11
Liquidity funds			5,401				5,229				5,556				5,093				5,142
Total assets under management				$23,158				$23,596				$24,764				$18,062				$18,849
Client assets under administration			10,867				11,783				12,860				13,183				13,760
Total assets				$34,025				$35,379				$37,624				$31,245				$32,609
Investment Advisors:
Equity/Fixed Income programs				$30,032				$30,881				$33,189				$34,831				$35,618
Collective Trust Fund programs			532				158				14				14				14
Liquidity funds			1,886				2,176				2,085				2,028				2,520
Total assets under management				$32,450				$33,215				$35,288				$36,873				$38,152
Institutional Investors:
Equity/Fixed Income programs				$57,763				$61,304				$63,642				$63,466				$63,153
Collective Trust Fund programs			284				120				101				105				107
Liquidity funds			3,253				3,493				2,960				2,975				3,091
Total assets under management				$61,300				$64,917				$66,703				$66,546				$66,351
Investment Managers:
Equity/Fixed Income programs				$62				$68				$68				$75				$76
Collective Trust Fund programs			14,797				15,719				17,129				18,205				19,259
Liquidity funds			287				395				511				500				613
Total assets under management				$15,146				$16,182				$17,708				$18,780				$19,948
Client assets under administration			237,155				240,520				263,054				286,018				292,627
Total assets				$252,301				$256,702				$280,762				$304,798				$312,575
Investments in New Businesses:
Equity/Fixed Income programs				$530				$518				$542				$567				$584
Liquidity funds			35				33				38				34				27
Total assets under management				$565				$551				$580				$601				$611
LSV Asset Management:
Equity/Fixed Income programs				$57,164				$59,383				$63,997				$66,781				$69,463
Total:
Equity/Fixed Income programs (A)				$163,078				$170,455				$180,635				$178,679				$182,590
Collective Trust Fund programs			15,843				16,063				17,255				18,334				19,391
Liquidity funds			10,862				11,326				11,150				10,630				11,393
Total assets under management				$189,783				$197,844				$209,040				$207,643				$213,374
Client assets under administration			248,022				252,303				275,914				299,201				306,387
Total assets				$437,805				$450,147				$484,954				$506,844				$519,761

(A)	Equity/Fixed Income programs in the Private Banks segment for 2012 and first-quarter 2013 included average assets related to SEI Asset Korea, which was sold in first-quarter 2013. Average assets for SEI Asset Korea for the third and fourth quarters of 2012 were $6.5 billion and $6.8 billion, respectively, and $7.0 billion for the first-quarter 2013.

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