ASEH — Earnings Release 2025

Dec 8, 2025

Third Quarter 2025 Earnings Release

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ASE Technology Holding

30 October, 2025

Safe Harbor Notice

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This presentation contains "forward-looking statements" within the meaning of Section 27A of the United States Securities Act of 1933, as amended, and Section 21E of the United States Securities Exchange Act of 1934, as amended. These statements are made under the “safe harbor” provisions of the U.S. Private Securities Litigation Reform Act of 1995. Although these forward-looking statements, which may include statements regarding our future results of operations, financial condition or business prospects, are based on our own information and information from other sources we believe to be reliable, you should not place undue reliance on these forward-looking statements, which apply only as of the date of this presentation. The words “anticipate,” “believe,” “estimate,” “expect,” “intend,” “plan” and similar expressions, as they relate to us, are intended to identify these forward-looking statements in this presentation. These forward-looking statements are necessarily estimates reflecting the best judgment of our senior management and our actual results of operations, financial condition or business prospects may differ materially from those expressed or implied by the forward-looking statements for reasons including, among others, risks associated with cyclicality and market conditions in the semiconductor or electronic industry; changes in our regulatory environment, including our ability to comply with new or stricter environmental regulations and to resolve environmental liabilities; demand for the outsourced semiconductor packaging, testing and electronic manufacturing services we offer and for such outsourced services generally; the highly competitive semiconductor or manufacturing industry we are involved in; our ability to introduce new technologies in order to remain competitive; international business activities; our business strategy; our future expansion plans and capital expenditures; the strained relationship between the Republic of China and the People’s Republic of China; general economic and political conditions; the recent shift in United States trade policies; possible disruptions in commercial activities caused by natural or human-induced disasters; fluctuations in foreign currency exchange rates; and other factors. For a discussion of these risks and other factors, please see the documents we file from time to time with the Securities and Exchange Commission, including the 2024 Annual Report on Form 20-F filed on March 27, 2025.

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Consolidated Statements of Income

Quarterly Comparison (Unaudited)

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(NT$ million) Q3 / 2025 % Q2 / 2025 % Q3 / 2024 % QoQ YoY
Net Revenues:
ATM 99,393 59.0% 91,648 60.8% 84,545 52.8% 8% 18%
EMS 68,405 40.6% 58,374 38.7% 74,871 46.8% 17% -9%
Others 771 0.4% 728 0.5% 689 0.4% 6% 12%
Total Net Revenues 168,569 100.0% 150,750 100.0% 160,105 100.0% 12% 5%
Gross Profit 28,877 17.1% 25,687 17.0% 26,426 16.5% 12% 9%
Operating Income (Loss) 13,201 7.8% 10,193 6.8% 11,470 7.2% 30% 15%
Pretax Income (Loss) 13,976 8.3% 9,255 6.1% 12,325 7.7% 51% 13%
Income Tax Benefit (Expense) (2,615) -1.6% (1,576) -1.0% (2,052) -1.3%
Non-controlling Interests (491) -0.3% (158) -0.1% (540) -0.3%
Net Income Attributable to
10,870 6.4% 7,521 5.0% 9,733 6.1% 45% 12%
Shareholders of the Parent
Basic EPS(NT$) 2.50 1.74 2.25 44% 11%
Diluted EPS(NT$) 2.41 1.70 2.18 42% 11%
Additional Commentary From Management:
Gross Profit excl. PPA expenses 29,392 17.4% 26,208 17.4% 27,360 17.1% 12% 7%
Operating Income excl. PPA expenses 13,979 8.3% 10,974 7.3% 12,668 7.9% 27% 10%
Net income attributable to
shareholders of the parent excl. PPA 11,629 6.9% 8,288 5.5% 10,906 6.8% 40% 7%
expenses
Basic EPS(NT$) excl. PPA expenses 2.68 1.91 2.52 40% 6%
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Consolidated Operations

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(Unaudited)

0 30,000 60,000 90,000 120,000 150,000 180,000 NT$ million	0 30,000 60,000 90,000 120,000 150,000 180,000 NT$ million	0 30,000 60,000 90,000 120,000 150,000 180,000 NT$ million	72,862 59,326 15.7% 5.6%	72,862 59,326 15.7% 5.6%	72,862 59,326 15.7% 5.6%	76,676 62,853 16.4% 6.4%	84,545 74,871 16.5% 7.2%	84,545 74,871 16.5% 7.2%	84,545 74,871 16.5% 7.2%	87,208 74,243 16.4% 6.9%	85,606 91,648 61,860 58,374 16.8% 17.0% 6.5% 6.8%	85,606 91,648 61,860 58,374 16.8% 17.0% 6.5% 6.8%	85,606 91,648 61,860 58,374 16.8% 17.0% 6.5% 6.8%
													68,405 17
							74,871 16			74,243 16
											61,860 16
						62,853 16
			59,326 15
													99,393 7.8
							84,545 7.2			87,208 6.	85,606 6.
						76,676 6.
			72,862 5.
			Q1/24			Q2/24	Q3/24			Q4/24	Q1/25 Q2/25
					ATM Revenue				EMS Revenue
				Gross Margin

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ATM Statements of Income

Quarterly Comparison (Unaudited)

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(NT$ million) Q3 / 2025 % Q2 / 2025 % Q3 / 2024 % QoQ YoY
Net Revenues:
Packaging 80,602 80.4% 74,440 80.4% 70,290 81.9% 8% 15%
Testing 18,420 18.3% 16,612 18.0% 14,124 16.5% 11% 30%
Direct Material 1,190 1.2% 1,431 1.5% 1,295 1.5% -17% -8%
Others 77 0.1% 82 0.1% 81 0.1% -6% -5%
Total Net Revenues 100,289 100.0% 92,565 100.0% 85,790 100.0% 8% 17%
Gross Profit 22,697 22.6% 20,248 21.9% 19,795 23.1% 12% 15%
Operating Income (Loss) 10,862 10.8% 8,817 9.5% 9,219 10.7% 23% 18%
Additional Commentary From Management:
Gross Profit excl. PPA expenses 23,187 23.1% 20,751 22.4% 20,689 24.1% 12% 12%
Operating Income excl. PPA expenses 11,602 11.6% 9,569 10.3% 10,363 12.1% 21% 12%
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ATM Operations

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(Unaudited)

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NT$ million
120,000 40%
100,289
100,000 92,565
88,363
85,790 86,668
30%
22,697
77,813
80,000 73,908 20,248
20,609 19,611
19,795
17,201
15,557
23.3%
60,000 22.1% 23.1% 22.6% 21.9% 22.6% 20%
21.0%
40,000
10%
20,000
0 0%
Q1/24 Q2/24 Q3/24 Q4/24 Q1/25 Q2/25 Q3/25
Revenue Gross Profit Gross Margin
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ATM Revenues by Application

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(Unaudited)

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100%
30% 32% 32% 30% 30% 30% 30%
80%
60% 18% 17%
19% 18% 22% 24% 25%
40%
52% 49% 50% 53% 48% 46% 45%
20%
0%
Q1/24 Q2/24 Q3/24 Q4/24 Q1/25 Q2/25 Q3/25
Communication Computing Automotive, Consumer & Others
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ATM Revenues by Type

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(Unaudited)

0% 20% 40% 60% 80% 100%	43% 44% 45% 47% 46% 47% 48% 30% 31% 29% 27% 28% 28% 26% 9% 7% 8% 7% 6% 5% 6% 16% 16% 16% 18% 18% 18% 18% 2% 2% 2% 1% 2% 2% 2% Q1/24 Q2/24 Q3/24 Q4/24 Q1/25 Q2/25 Q3/25 Material Testing Others Wirebonding Bump/FC/WLP /SiP

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EMS Operations

Quarterly Comparison & Revenues by Application (unaudited)

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(unaudited)	(unaudited)	(unaudited)	(unaudited)	(unaudited)	(unaudited)	(unaudited)
(NT$ million) EMS Net Revenues Gross Profit Operating Income (Loss) 3% 100%							Q3 / 2025 69,022 6,379 2,541			% 100.0% 9.2% 3.7%			Q2 / 2025		% 100.0% 9.4% 2.6%			Q3 / 2024			% 100.0% 9.0% 3.3%			QoQ YoY 17% -8% 15% -6% 68% 4% 2%
													58,770 5,549 1,513					75,384 6,757 2,453
	100%	3%					3%			1%			2%					2%			2%			2%
	0% 20% 40% 60% 80%		12%					11%			9%			8%				10%				9%			7%
											11%			11%				12%				14%			12%
			12%					13%
											36%			33%											40%
			27%					29%										33%				32%
			12%											9%
								11%			9%							10%				10%
																									9%
														37%
			34%					33%			34%							33%				33%
																									30%
		Q1/24 Q2/24 Q3/24 Communication Industrial					Q2/24			Q3/24			Q4/24 Q1/25								Q2/25
				Communication Industrial									Computing Consumer Automotive Others
						Communication							Computing

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Key Balance Sheet Items & Indices

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(Unaudited)

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(NT$ million) Sept. 30, 2025 Jun. 30, 2025
Cash and cash equivalent $75,142 $72,785
Financial assets - current 8,270 4,118
Financial assets - non current & investments - equity method 41,678 38,409
Property, plant & equipment 397,195 364,849
Total assets 842,644 765,175
Short-term loans & short-term bills payable 59,976 40,369
Current portion of bonds payable 3,499 8,499
Current portion of long-term loans 4,338 4,431
Bonds payable 17,370 16,668
Long-term loans & long-term bills payable 201,577 162,326
Total interest bearing debts 295,682 240,132
Total liabilities 503,091 450,240
Total equity (Including non-controlling interest) 339,553 314,935
Quarterly EBITDA 32,613 27,426
Current ratio 1.13 1.02
Net debt to equity ratio 0.63 0.52
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*: EBITDA stands for net income or loss before interest, taxes, depreciation, amortization, impairment and investment gain or loss as well as other items.

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Equipment Capital Expenditures vs. EBITDA (Unaudited)

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US$ million
1,200
1,095
992
1,000
888 895 892 879
843
811
765 779
800
640
603
600
406
400
228
200
0
Q1/24 Q2/24 Q3/24 Q4/24 Q1/25 Q2/25 Q3/25
Capex EBITDA
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Fourth Quarter 2025 Outlook (1/2)

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Based on our current business outlook and exchange rate assumptions of 1 US dollar to 30.4 NT dollars (versus 29.7 in 3[rd] quarter 2025), management projects overall performance for the fourth quarter of 2025 to be as follows:

◼ Consolidated

• In NT dollar terms, our consolidated 4th quarter revenue should grow by 1 to 2 percent quarter over quarter;

• Our consolidated 4th quarter gross margin should increase by 70 to 100 basis points quarter over quarter;

• Our consolidated 4th quarter operating margin should increase by 70 to 100 basis points quarter over quarter.

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Fourth Quarter 2025 Outlook (2/2)

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Based on our current business outlook and exchange rate assumptions of 1 US dollar to 30.4 NT dollars (versus 29.7 in 3[rd] quarter 2025), management projects overall performance for the fourth quarter of 2025 to be as follows:

◼ ATM

• In NT dollar terms, our ATM 4th quarter revenue should grow by 3 to 5 percent quarter over quarter;

• Our ATM 4th quarter gross margin should increase by 100 to 150 basis points quarter over quarter.

◼ EMS

• In NT dollar terms, our EMS 4th quarter revenue should stay flat or decline slightly quarter over quarter;

• Our EMS 4th quarter operating margin should be similar to 4th quarter 2024 levels.

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Thank you

Appendix 1

Consolidated Statements of Comprehensive Income

(Unaudited)

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(NT$ thousand) Q1/ 2025 [1&2] Q2/ 2025 [1&2] Q3/ 2025 [1&2]
Revenues 148,153,262 150,750,323 168,568,888
COGS 123,260,526 125,062,803 139,692,147
PPA under COGS 557,027 520,681 515,185
Gross profit 24,892,736 25,687,520 28,876,741
Gross profit excl. PPA 25,449,763 26,208,201 29,391,926
OPEX 15,221,435 15,494,438 15,676,044
PPA under OPEX 262,652 260,038 262,807
Operating income 9,671,301 10,193,082 13,200,697
Operating income excl. PPA 10,490,980 10,973,801 13,978,689
Non Op gain/(loss) 138,628 (938,600) 775,540
PPA under Non Op gain/ (loss) 61 959 155
Non Op gain/ (loss) excl. PPA 138,689 (937,641) 775,695
Pretax income 9,809,929 9,254,483 13,976,238
PPA under Pretax income 819,740 781,678 778,147
Pretax income excl. PPA 10,629,669 10,036,161 14,754,385
Tax expenses 2,021,624 1,575,805 2,615,170
PPA under Tax expense (12,964) (9,337) (10,837)
Tax expense excl. PPA 2,034,588 1,585,142 2,626,007
Non-controlling interests 234,472 157,593 491,305
PPA under Non-controlling interests 8,408 5,811 8,129
Non-controlling interests excl. PPA 242,880 163,404 499,434
Net income attributable to shareholders of
7,553,833 7,521,085 10,869,763
the parent
PPA expenses under Net income
798,368 766,530 759,181
attributable to shareholders of the parent
Net income attributable to shareholders of
8,352,201 8,287,615 11,628,944
the parent excl. PPA
Total PPA expenses 806,776 772,341 767,310
Basic EPS (NT$) 1.75 1.74 2.50
Basic EPS (NT$) excl. PPA 1.93 1.91 2.68
Diluted EPS (NT$) 1.64 1.70 2.41
Diluted EPS (NT$) excl. PPA 1.82 1.88 2.58
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1: PPA expenses are the P&L impacts from the accounting treatment of purchase price allocation in relation to the ASE/SPIL and ASE/Infineon transaction, which resulted in increased asset values from purchase price premiums in inventory, PP&E, intangibles, right-of-use assets, other assets, and deferred tax liability. The PPA expenses excluded are related to depreciation, amortization, other expenses, and income tax benefit $0.77bn in 1Q25, $0.75bn in 2Q25, and $0.74bn in 3Q25. 2: PPA expenses are the P&L impacts from the accounting treatment of purchase price allocation in relation to the USI/Asteelflash and USI/Hirschmann transaction, which resulted in increased asset and liability values from purchase price premiums in inventory, PP&E, intangibles, right-of-use assets and deferred tax liability. The PPA expenses excluded are related to depreciation, amortization, other expenses and income tax benefit $0.04bn in 1Q25, $0.02bn in 2Q25, and $0.03bn in 3Q25.

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