本研究旨在探討下游客戶於年報「管理層討論與分析（MD&A）」中所使用的正面敘述語調，是否會跨期影響上游供應商針對雙方合作所投入的「關係特定投資（RSI）」。透過分析 2000 至 2024 年美國上市企業數據，實證發現客戶年報的文字語調越正面，確實會顯著帶動供應商在下一期增加實質的研發費用投資，這證實了質化文本能跨越企業邊界傳遞前瞻性的經濟訊號，並實質指引供應商的投資決策。 為了進一步檢務現實商業環境對此跨期影響力的干擾，本研究引入了三大類調節變數進行分析：包含「供銷關係強度」（客戶的不可替代性與重要性）、「供應鏈資訊環境」（共同分析師、共同機構投資人及共同地理環境），以及「MD&A揭露屬性」（時效性、可信度與資訊內涵）。實證結果顯示，主要有兩類機制會顯著反向削弱上述的引導效果：第一是供應鏈資訊環境中的「共同機構投資人」與「共同地理環境」，當供銷雙方背後擁有共同的機構大股東或地理位置接近時，會引發強烈的「資訊替代機制」，亦即專業機構大股東與在地私下密集的溝通管道能提供更即時、深層的營運底細，這會大幅取代並擠出供應商對公開年報文本語調的邊際依賴度；第二是揭露屬性中的「時效性」，當客戶越快完成年報申報（時效性越高）時，過快發布的文字反而可能包含較多未經證實的營運雜訊與不確定性，促使供應商在進行長期實體投資時態度轉趨保守，進而削弱了正面語調原本的引導功能。 至於其餘的調節變數（如客戶的不可替代性與重要性、共同分析師、可信度與資訊內涵），則可能受限於實務上長期供貨合約的剛性制約、分析師雙重機制的動態抵銷、客戶前一年度會計預測等歷史不足以動搖長期實體戰略，或是跨資料庫串接導致樣本數嚴重縮減等現實因素，在統計上皆未達顯著的調節水準。總結來說，這篇論文證實了客戶年報的質性語調確實具備引導供應鏈上游實體投資的實質能力，但其實際發揮的成效會深受私有資訊管道（共同機構投資人與地理鄰近性）之替代效應以及資訊品質（時效性雜訊）等現實條件的牽制。;This study aims to investigate whether the positive narrative tone used by downstream customers in the Management′s Discussion and Analysis (MD&A) of their annual reports intertemporally affects the relationship-specific investments (RSI) made by upstream suppliers for their mutual cooperation. By analyzing data from U.S. listed companies between 2000 and 2024， the empirical results reveal that a more positive textual tone in the customer′s annual report significantly drives the supplier to increase their substantial research and development investments in the subsequent period. This confirms that qualitative texts can cross corporate boundaries to transmit forward-looking economic signals and substantively guide suppliers′ investment decisions. To further examine the interference of the real-world business environment on this intertemporal influence， this study introduces three main categories of moderating variables for analysis: supply-demand relationship strength， supply chain information environment， and disclosure attributes. The empirical results show that two main mechanisms significantly and negatively weaken the aforementioned guiding effect. The first is common institutional investors and geographic proximity within the supply chain information environment. When both parties share common major institutional shareholders or are geographically close， a strong information substitution mechanism is triggered; that is， professional institutional shareholders and dense local private communication channels provide more immediate and in-depth operational details， which largely replaces and crowds out the supplier′s marginal reliance on the textual tone of public annual reports. The second is timeliness among the disclosure attributes. When the customer completes the annual report filing faster， the prematurely released texts may instead contain more unverified operational noise and uncertainty， prompting the supplier to adopt a more conservative attitude when making long-term real investments， thereby weakening the original guiding function of the positive tone. As for the remaining moderating variables， they may be constrained by practical factors such as the rigid restrictions of long-term supply contracts， the dynamic offsetting of dual analyst mechanisms， the insufficiency of customers′ prior-year accounting forecasts and historical records to sway long-term real strategies， or a severe reduction in sample size caused by cross-database merging， and thus do not reach a statistically significant moderating level. In conclusion， this paper confirms that the qualitative tone of customers′ annual reports indeed possesses the substantive ability to guide upstream real investments in the supply chain， but its actual effectiveness is profoundly constrained by real-world conditions such as the substitution effect of private information channels and information quality.
